Techniques for percutaneous mitral valve replacement and sealing

CROSS-REFERENCES TO RELATED APPLICATIONS

The present application claims priority and is a continuation-in-part of:

(a) U.S. Ser. No. 12/840,463 to Hacohen, filed Jul. 21, 2010, entitled “Guide wires with commissural anchors to advance a prosthetic valve,” which published as US 2012/0022639, (b) U.S. Ser. No. 13/033,852 to Gross, filed Feb. 24, 2011, entitled “Techniques for percutaneous mitral valve replacement and sealing,” which published as US 2012/0022640, and which is a continuation-in-part of U.S. Ser. No. 12/840,463 to Hacohen; and

claims priority from U.S. Provisional Patent Application 61/492,449 to Gross, filed Jun. 2, 2011, entitled, “Techniques for percutaneous mitral valve replacement and sealing.”

All of the above-referenced applications are incorporated herein by reference.

FIELD OF THE INVENTION

Embodiments of the present invention relate in general to valve replacement. More specifically, embodiments of the present invention relate to prosthetic valves for replacement of an atrioventricular valve.

BACKGROUND

Dilation of the annulus of the mitral valve prevents the valve leaflets from fully coapting when the valve is closed. Regurgitation of blood from the ventricle into the atrium results in increased total stroke volume and decreased cardiac output, and ultimate weakening of the ventricle secondary to a volume overload and a pressure overload of the atrium. Dilation of the annulus is sometimes treated by implanting a prosthetic mitral valve at a patient's native mitral valve.

SUMMARY

For some applications of the present invention, one or more guide members (e.g., wires, sutures, or strings) is configured to be anchored to respective commissures of a native atrioventricular valve of a patient, and each guide member facilitates the advancement therealong of respective commissural anchors. The commissural anchors are shaped so as to define a plurality of barbs or prongs which are expandable to restrict proximal movement of the anchors following their deployment. The guide members facilitate advancement of a collapsible prosthetic valve support (e.g., a skirt) which serves as a base for and receives a collapsible prosthetic mitral valve which is subsequently coupled to the support. The support comprises a proximal annular element, or ring, and a distal cylindrical element. The cylindrical element is configured to push aside and press against the native leaflets of the native valve, and the proximal annular element is shaped so as to define one or more holes for sliding the valve support along the one or more guide members. The proximal annular element is configured to be positioned along the annulus of the native valve.

The collapsible prosthetic valve is configured for implantation in and/or at least partial replacement (e.g., full replacement) of the native atrioventricular valve of the patient, such as a native mitral valve or a native tricuspid valve. The valve support and the prosthetic valve are configured to assume collapsed states for minimally-invasive delivery to the diseased native valve, such as by percutaneous or transluminal delivery using one or more catheters. For some applications, the valve support and the prosthetic valve are implanted during an open-heart procedure.

The prosthetic valve support is shaped so as to define a downstream skirt. The downstream skirt is configured to be placed at native valve, such that the downstream skirt passes through the orifice of the native valve and extends toward, and, typically partially into, a ventricle. The downstream skirt typically additionally pushes aside and presses against the native leaflets of the native valve, which are left in place during and after implantation of the prosthetic valve support and/or the prosthetic valve.

The proximal annular element has upper and lower surfaces. For some applications of the present invention, one or more, e.g., a plurality of, tissue anchors are coupled to the lower surface and facilitate anchoring of the proximal annular element to the annulus of the native valve. For some applications, the one or more anchors comprise at least first and second commissural anchors that are configured to be implanted at or in the vicinity of the commissures of the native valve.

The cylindrical element of the valve support has first and second ends and a cylindrical body disposed between the first and second ends. The first end of the cylindrical element is coupled to the annular element while the second end defines a free end of the cylindrical element. For some applications of the present invention, the cylindrical element of the valve support is invertible such that (1) during a first period, the second end and the cylindrical body of the cylindrical element are disposed above the annular element (e.g., in the atrium of the heart), and (2) during a second period, the second end and the cylindrical body of the cylindrical element are disposed below the annular element (e.g., in the ventricle of the heart).

For some applications, techniques are applied to facilitate sealing of the interface between the valve support and the native valve, and/or the interface between the prosthetic valve and the native valve. For example, a sealing balloon may be placed on a valve-facing, lower side of the annular element of the valve support, the sealing balloon being configured to be inflated such that the balloon seals the interface between the valve support and the native valve. Alternatively or additionally, commissural helices are wrapped around chordae tendineae of the patient in order to facilitate sealing of the valve commissures around the valve support and/or around the valve. Further alternatively or additionally, the valve commissures are grasped by grasping elements that act in order to facilitate sealing of the commissures around the valve support and/or around the valve. For some applications, one or more of the aforementioned sealing elements facilitates anchoring of the prosthetic valve to the native valve in addition to facilitating sealing.

For some applications, the prosthetic valve comprises an expandable frame (e.g., a wire frame), and a sealing material (such as latex) is disposed on the outer surface of the frame so as to form webbing between at least some of the struts of the wire frame, and to provide sealing between the wire frame and the native valve.

For some applications, an invertible prosthetic valve support is used to support a prosthetic valve. Typically, a sealing element is disposed circumferentially around a surface of the invertible prosthetic valve support that is initially an inner surface of the invertible prosthetic valve support. The invertible prosthetic valve support is anchored to the native valve, and is subsequently inverted. Subsequent to the inversion of the invertible prosthetic valve support, the sealing element is disposed on the outer surface of the invertible prosthetic valve support and acts to seal the interface between the outer surface and the native valve.

There is therefore provided, in accordance with some applications of the present invention, apparatus, including:

a prosthetic valve support configured to be placed at an annulus of a native atrioventricular valve of a patient, the prosthetic valve support defining an annular element that defines an inner cross-sectional area thereof;

an expandable prosthetic valve configured to be placed into a ventricle of the patient, the prosthetic valve including: <ul id="ul0001" list-style="none"><li id="ul0001-0001" num="0000"><ul id="ul0002" list-style="none"><li id="ul0002-0001" num="0018">an expandable frame; and</li><li id="ul0002-0002" num="0019">prosthetic valve leaflets coupled to the expandable frame;</li></ul></li></ul>

the expandable frame of the prosthetic valve being configured such that when the frame is in a non-constrained state thereof, a cross-sectional area of the frame, along at least a given portion of a length of the frame, is greater than the cross-sectional area defined by the annular element of the prosthetic valve support,

the prosthetic valve thereby being couplable to the prosthetic valve support at any location along the portion, responsively to radial forces acted upon the valve support by the expandable frame, by the expandable frame being expanded when the location along the portion is aligned with the annular element of the prosthetic valve support.

For some applications, the valve support is collapsible for transcatheter delivery.

For some applications, the native atrioventricular valve includes a mitral valve, and the prosthetic valve includes three prosthetic leaflets.

For some applications, the annular element of the valve support is asymmetrically shaped.

For some applications, the annular element is shaped to define a hole, and a center of the hole is disposed asymmetrically with respect to an outer perimeter of the annular element.

For some applications, the frame includes proximally-facing protrusions at a distal end thereof, the protrusions being configured to prevent proximal migration of the valve into an atrium.

For some applications, the protrusions are disposed at an angle from the frame of more than 40 degrees.

For some applications, the protrusions are disposed at an angle from the frame of less than 80 degrees.

For some applications, a length of each of the protrusions is less than 5 mm.

For some applications, the frame includes a single proximally-facing protrusion corresponding to each native valve leaflet of the valve, each of the protrusions having a width of less than 1 mm.

For some applications, the protrusions are disposed in a sinusoidal configuration such that the protrusions conform with a saddle shape of the patient's native annulus.

For some applications, the protrusions are configured to prevent the native leaflets from interfering with a left ventricular outflow tract of the patient.

For some applications, the frame includes first and second sets of one or more protrusions, each set of protrusions configured to ensnare a respective native leaflet of the native valve of the patient, the first set of protrusions being disposed within a first circumferential arc with respect to a longitudinal axis of the prosthetic valve, on a first side of a distal end of the frame, the second set of protrusions being disposed within a second circumferential arc with respect to the longitudinal axis of the prosthetic valve, on a second side of the distal end of the frame, the first and second sets being disposed so as to provide first and second gaps therebetween at the distal end of the frame, at least one of the gaps having a circumferential arc of at least 20 degrees, the apparatus further including one or more valve guide members configured to be delivered to one or more commissures of the native valve, and to guide the valve such that the first and second circumferential arcs are aligned with respective leaflets of the native valve and such that the first and second gaps are aligned with respective commissures of the native valve.

For some applications, the at least one of the gaps has a circumferential arc of at least 60 degrees.

For some applications, the first circumferential arc defines an angle of between 25 degrees and 90 degrees about the longitudinal axis of the prosthetic valve.

For some applications, the second circumferential arc defines an angle of between 25 degrees and 90 degrees about the longitudinal axis of the prosthetic valve.

For some applications, the first circumferential arc defines an angle of between 45 degrees and 75 degrees about the longitudinal axis of the prosthetic valve.

For some applications, the second circumferential arc defines an angle of between 45 degrees and 75 degrees about the longitudinal axis of the prosthetic valve.

For some applications, the expandable frame of the prosthetic valve is configured such that when the frame is in a non-constrained state thereof the frame has a maximum diameter of less than 25 mm.

For some applications, the expandable frame of the prosthetic valve is configured such that when the frame is in a non-constrained state thereof the frame has a maximum diameter of more than 15 mm.

For some applications, the expandable frame of the prosthetic valve is configured such that when the frame is in a non-constrained state thereof the frame has a maximum diameter of less than 20 mm.

For some applications, the expandable frame of the prosthetic valve is configured such that when the frame is in a non-constrained state thereof, a cross-sectional area of the frame at a proximal end of the frame is greater than a cross-sectional area of the frame at a distal end of the frame.

For some applications, the expandable frame of the prosthetic valve is configured such that when the frame is in the non-constrained state thereof the frame defines a frustoconical shape.

For some applications, the expandable frame of the prosthetic valve is configured such that when the frame is in the non-constrained state thereof the frame defines a trumpet shape.

There is further provided, in accordance with some applications of the present invention, a method, including:

placing a prosthetic valve support at an annulus of a native atrioventricular valve of a patient, the prosthetic valve support defining an annular element that defines an inner cross-sectional area thereof;

placing into a ventricle of the patient, an expandable prosthetic valve, <ul id="ul0003" list-style="none"><li id="ul0003-0001" num="0000"><ul id="ul0004" list-style="none"><li id="ul0004-0001" num="0048">the prosthetic valve including an expandable frame, and prosthetic valve leaflets coupled to the expandable frame,</li><li id="ul0004-0002" num="0049">the expandable frame of the prosthetic valve being configured such that when the frame is in a non-constrained state thereof, a cross-sectional area of the frame, along at least a given portion of a length of the frame, is greater than the cross-sectional area defined by the annular element of the prosthetic valve support;</li></ul></li></ul>

determining a location anywhere along the portion at which to couple the expandable valve the prosthetic valve support; and

in response thereto,

aligning the location along the portion of the expandable frame with the annular element of the prosthetic valve support; and

coupling the expandable valve to the prosthetic valve support at the location, responsively to radial forces acted upon the valve support by the expandable frame, by facilitating expansion of the expandable frame, when the location along the portion is aligned with the annular element of the prosthetic valve support.

For some applications, placing the valve support at the annulus includes transcatheterally placing the valve support at the annulus in a collapsed state.

For some applications, the native atrioventricular valve includes a mitral valve, and placing the prosthetic valve into the ventricle includes placing into the ventricle a prosthetic valve that includes three prosthetic leaflets.

For some applications, placing the prosthetic valve support at the annulus includes placing an asymmetrically-shaped prosthetic valve support at the annulus.

For some applications, placing the prosthetic valve support at the annulus includes placing at the annulus an annular element that is shaped to define a hole, a center of the hole being disposed asymmetrically with respect to an outer perimeter of the annular element, the annular element being placed such that a center of the hole is disposed asymmetrically with respect to the annulus.

For some applications, the frame includes proximally-facing protrusions at a distal end thereof, the protrusions being configured to prevent proximal migration of the valve into an atrium, and coupling the expandable valve to the prosthetic valve support includes preventing proximal migration of the valve by coupling the valve to the valve support such that the leaflets are disposed at least partially between the protrusions and the valve support.

For some applications, coupling the expandable valve to the prosthetic valve support includes preventing the native leaflets from interfering with a left ventricular outflow tract of the patient.

For some applications, coupling the expandable valve to the prosthetic valve support includes allowing movement of the leaflets with respect to the frame while preventing the proximal migration of the valve.

For some applications, the frame includes first and second sets of one or more protrusions, each set of protrusions configured to ensnare a respective native leaflet of the native valve of the patient, the first set of protrusions being disposed within a first circumferential arc with respect to a longitudinal axis of the prosthetic valve, on a first side of a distal end of the frame, the second set of protrusions being disposed within a second circumferential arc with respect to the longitudinal axis of the prosthetic valve, on a second side of the distal end of the frame, the first and second sets being disposed so as to provide first and second gaps therebetween at the distal end of the frame, at least one of the gaps having a circumferential arc of at least 20 degrees, the method further including guiding the valve such that the first and second circumferential arcs are aligned with respective leaflets of the native valve and such that the first and second gaps are aligned with respective commissures of the native valve.

For some applications, facilitating expansion of the frame includes facilitating expansion of the frame to a maximum diameter of less than 25 mm.

For some applications, facilitating expansion of the frame includes facilitating expansion of the frame to a maximum diameter of more than 15 mm.

For some applications, facilitating expansion of the frame includes facilitating expansion of the frame to a maximum diameter of less than 20 mm.

For some applications, facilitating expansion of the frame includes facilitating expansion of the frame such that a cross-sectional area of the frame at a proximal end of the frame is greater than a cross-sectional area of the frame at a distal end of the frame.

For some applications, facilitating expansion of the frame includes facilitating expansion of the frame such that the frame defines a frustoconical shape.

For some applications, facilitating expansion of the frame includes facilitating expansion of the frame such that the frame defines a trumpet shape.

There is additionally provided, in accordance with some applications of the present invention, a method, including:

determining an indication of an area defined by an annulus of a native atrioventricular valve of a patient;

selecting a prosthetic valve support by determining that the prosthetic valve support defines an annular element that defines an inner cross-sectional area that is less than the area defined by the annulus;

placing the prosthetic valve support at the annulus of the native atrioventricular valve;

placing into a ventricle of the patient, an expandable prosthetic valve, the prosthetic valve including an expandable frame, and prosthetic valve leaflets coupled to the expandable frame;

coupling the expandable valve to the prosthetic valve support at the location, responsively to radial forces acted upon the valve support by the expandable frame, by facilitating expansion of the expandable frame,

a cross-sectional area defined by the expandable frame of the prosthetic valve being limited by the cross-sectional area defined by the annular element of the prosthetic valve support, such as to facilitate sealing of the native valve with respect to the prosthetic valve by facilitating closing of leaflets of the native valve around the prosthetic valve, upon deployment of the prosthetic valve.

For some applications, facilitating closing of leaflets of the native valve around the prosthetic valve includes facilitating sealing of the native valve at commissures of the native valve.

For some applications, facilitating closing of leaflets of the native valve around the prosthetic valve includes facilitating closing of the leaflets of the native valve around an outer surface of the expandable frame.

For some applications, placing the valve support at the annulus includes transcatheterally placing the valve support at the annulus in a collapsed state.

For some applications, the native atrioventricular valve includes a mitral valve, and placing the prosthetic valve into the ventricle includes placing into the ventricle a prosthetic valve that includes three prosthetic leaflets.

For some applications, placing the prosthetic valve support at the annulus includes placing an asymmetrically-shaped prosthetic valve support at the annulus.

For some applications, placing the prosthetic valve support at the annulus includes placing at the annulus an annular element that is shaped to define a hole, a center of the hole being disposed asymmetrically with respect to an outer perimeter of the annular element, the annular element being placed such that a center of the hole is disposed asymmetrically with respect to the annulus.

For some applications, the frame includes proximally-facing protrusions at a distal end thereof, the protrusions being configured to prevent proximal migration of the valve into an atrium, and coupling the expandable valve to the prosthetic valve support includes preventing proximal migration of the valve by coupling the valve to the valve support such that the leaflets are disposed at least partially between the protrusions and the valve support.

For some applications, coupling the expandable valve to the prosthetic valve support includes preventing the native leaflets from interfering with a left ventricular outflow tract of the patient.

For some applications, coupling the expandable valve to the prosthetic valve support includes allowing movement of the leaflets with respect to the frame while preventing proximal migration of the valve.

For some applications, the frame includes first and second sets of one or more protrusions, each set of protrusions configured to ensnare a respective native leaflet of the native valve of the patient, the first set of protrusions being disposed within a first circumferential arc with respect to a longitudinal axis of the prosthetic valve, on a first side of a distal end of the frame, the second set of protrusions being disposed within a second circumferential arc with respect to the longitudinal axis of the prosthetic valve, on a second side of the distal end of the frame, the first and second sets being disposed so as to provide first and second gaps therebetween at the distal end of the frame, at least one of the gaps having a circumferential arc of at least 20 degrees, the method further including guiding the valve such that the first and second circumferential arcs are aligned with respective leaflets of the native valve and such that the first and second gaps are aligned with respective commissures of the native valve.

For some applications, facilitating expansion of the frame includes facilitating expansion of the frame to a maximum diameter of less than 25 mm.

For some applications, facilitating expansion of the frame includes facilitating expansion of the frame to a maximum diameter of more than 15 mm.

For some applications, facilitating expansion of the frame includes facilitating expansion of the frame to a maximum diameter of less than 20 mm.

For some applications, facilitating expansion of the frame includes facilitating expansion of the frame such that a cross-sectional area of the frame at a proximal end of the frame is greater than a cross-sectional area of the frame at a distal end of the frame.

For some applications, facilitating expansion of the frame includes facilitating expansion of the frame such that the frame defines a frustoconical shape.

For some applications, facilitating expansion of the frame includes facilitating expansion of the frame such that the frame defines a trumpet shape.

There is additionally provided, in accordance with some applications of the present invention, a method, including:

placing a prosthetic valve support at an annulus of a native atrioventricular valve of a patient;

placing a prosthetic valve into a ventricle of the patient, the prosthetic valve including protrusions at a distal end thereof;

ensnaring one or more native leaflets of the native valve of the patient with the protrusions; and

coupling the prosthetic valve to the native valve, <ul id="ul0005" list-style="none"><li id="ul0005-0001" num="0000"><ul id="ul0006" list-style="none"><li id="ul0006-0001" num="0096">by sandwiching native leaflets of the native valve between the protrusions and the valve support, by pulling the prosthetic valve proximally with respect to the valve support, and</li><li id="ul0006-0002" num="0097">while the native leaflets are sandwiched between the protrusions and the valve support, coupling the prosthetic valve to the valve support, by facilitating radial expansion of the prosthetic valve such that the prosthetic valve is held in place with respect to the valve support responsively to radial forces acted upon the valve support by the prosthetic valve.</li></ul></li></ul>

There is further provided, in accordance with some applications of the present invention, a method, including:

determining an indication of an area defined by an annulus of a native atrioventricular valve of a patient;

selecting a prosthetic valve to be placed in the native valve by determining that the valve defines a cross-sectional area that is less than 90% of the area defined by the annulus; and

deploying the prosthetic valve at the native valve,

the selecting of the prosthetic valve facilitating sealing of the native valve with respect to the prosthetic valve by facilitating closing of leaflets of the native valve around the prosthetic valve, upon deployment of the prosthetic valve.

For some applications, selecting the prosthetic valve includes selecting a prosthetic valve having a material disposed on an outer surface thereof.

For some applications, selecting the prosthetic valve includes selecting a prosthetic valve having a material that prevents tissue growth disposed on an outer surface thereof.

For some applications, selecting the prosthetic valve includes selecting a prosthetic valve having a material that promotes tissue growth disposed on an outer surface thereof.

For some applications, selecting the prosthetic valve to be placed in the native valve includes determining that the valve defines a cross-sectional area that is less than 80% of the area defined by the annulus.

For some applications, selecting the prosthetic valve to be placed in the native valve includes determining that the valve defines a cross-sectional area that is less than 60% of the area defined by the annulus.

There is further provided, in accordance with some applications of the present invention, apparatus, including:

one or more valve support guide members configured to be delivered to one or more commissures of a native atrioventricular valve of a patient;

one or more valve support anchors configured to be anchored to the one or more commissures of the native valve;

a prosthetic valve support advanceable toward the native valve along the one or more valve support guide members and anchored to the native valve at atgg least the one or more commissures; and

a prosthetic valve configured to be coupled to the valve support.

For some applications, the valve support is collapsible for transcatheter delivery and expandable to contact the native atrioventricular valve.

For some applications, the one or more valve support anchors are configured to be anchored to the one or more commissures from ventricular surfaces thereof.

For some applications, the one or more valve support guide members includes one valve support guide member that is looped through first and second commissures of the atrioventricular valve in a manner in which a looped portion of the valve support guide member is disposed in a ventricle of the patient and first and second free ends of the valve support guide member are accessible from a site outside a body of the patient.

For some applications, the one or more valve support anchors includes first and second tissue anchors, the first and second tissue anchors being configured to be anchored to respective first and second commissures of the atrioventricular valve of the patient.

For some applications:

the one or more valve support anchors each include one or more radially-expandable prongs, and

the one or more prongs are disposed within a sheath in a compressed state prior to the anchoring, and exposed from within the sheath in order to expand and facilitate anchoring of the valve support anchor to the respective commissures.

For some applications, the prosthetic valve includes two or more prosthetic leaflets.

For some applications, the native atrioventricular valve includes a mitral valve, and the prosthetic valve includes three prosthetic leaflets.

For some applications, the valve support guide members are removable from the patient following the anchoring of the prosthetic valve support at the atrioventricular valve.

For some applications, the valve support is shaped so as to define a distal portion which is configured to push aside, at least in part, native leaflets of the valve of the patient.

For some applications, the one or more valve support anchors are advanceable along the one or more valve support guide members.

For some applications, the valve support is shaped so as to define one or more holes, the one or more holes being configured to facilitate slidable passage therethrough of a respective one of the one or more valve support guide members.

For some applications, the prosthetic valve is shaped so as to define one or more snares configured to ensnare one or more native leaflets of the native valve of the patient.

For some applications, the one or more valve support anchors includes one or more ventricular anchors, and the apparatus further includes one or more atrial anchors, each atrial anchor being configured to be advanced toward an atrial surface of the valve support and anchor in place the valve support in a vicinity of a respective one of the ventricular anchors.

For some applications, the apparatus includes one or more delivery lumens, and:

each one of the one or more valve support anchors is removably coupled to a distal end of a respective delivery lumen,

the delivery lumen is configured to facilitate advancement of the one or more anchors along the one or more guide members, and

the delivery lumen is decoupled from the anchor following the anchoring of the anchor to the one or more commissures.

For some applications, the one or more valve support guide members are removable from the body of the patient following the advancement of the one or more anchors along the one or more guide members.

For some applications:

the valve support is shaped so as to define one or more holes,

the one or more holes are configured to facilitate slidable passage therethrough of a respective one of the one or more delivery lumens, and

the one or more delivery lumens are decoupleable from the respective valve support anchor following the anchoring of the valve support to at least the one or more commissures.

For some applications, the one or more delivery lumens are removable from the body of the patient following the anchoring of the valve support to at least the one or more commissures.

For some applications, the valve support includes an annular element and a generally cylindrical element coupled to the annular element, the generally cylindrical element being configured to push aside native leaflets of the native valve, the cylindrical element has first and second ends and a cylindrical body that is disposed between the first and second ends.

For some applications, the apparatus includes one or more annular element tissue anchors, the annular element has an upper surface and a lower surface, and the lower surface is coupled to the one or more annular element tissue anchors, the one or more annular element tissue anchors being configured to puncture tissue of a native annulus of the native valve of the patient.

For some applications, one or more annular element tissue anchors includes a plurality of annular element tissue anchors positioned around the lower surface of the annular element.

For some applications, the one or more annular element tissue anchors includes a first commissural anchor configured to puncture tissue of the native valve at a first commissure thereof, and a second commissural anchor configured to puncture tissue of the native valve at a second commissure thereof.

For some applications, each anchor of the one or more annular element tissue anchors includes a distal pointed tip and one or more radially-expandable prongs, the prongs being configured to expand and facilitate anchoring of the anchor and restrict proximal motion of the annular element tissue anchor.

For some applications, the apparatus includes one or more prosthetic valve guide members reversibly couplable to the cylindrical element in a vicinity of the second end of the cylindrical element, the prosthetic valve guide members being configured to facilitate advancement of the prosthetic valve therealong and toward the valve support.

For some applications: <ul id="ul0007" list-style="none"><li id="ul0007-0001" num="0000"><ul id="ul0008" list-style="none"><li id="ul0008-0001" num="0145">the first end of the cylindrical element is coupled to the annular element,</li><li id="ul0008-0002" num="0146">during a first period, the second end of the cylindrical element is disposed above the annular element in a manner in which the body of the cylindrical element is disposed above the annular element, and</li><li id="ul0008-0003" num="0147">the cylindrical element is invertible in a manner in which, during a second period, the second end of the cylindrical element is disposed below the annular element and the body of the cylindrical element is disposed below the annular element.</li></ul></li></ul>

For some applications:

during the first period, the second end of the cylindrical element is disposed in an atrium of a heart of the patient and the annular element is positioned along an annulus of the native valve,

the prosthetic valve is advanceable along the one or more prosthetic valve guide members into a ventricle of the heart of the patient, and

in response to advancement of the prosthetic valve into the ventricle, the one or more prosthetic valve guide members are pulled into the ventricle and pull the second end and the body of the cylindrical element into the ventricle to invert the cylindrical element.

There is further provided, in accordance with some applications of the present invention, a method, including:

advancing one or more valve support guide members toward one or more commissures of a native atrioventricular valve of a patient;

advancing along the one or more valve support guide members one or more valve support tissue anchors toward the one or more commissures;

anchoring the one or more valve support tissue anchors to the one or more commissures;

anchoring a prosthetic valve support at the native atrioventricular valve by anchoring the prosthetic valve support at at least the one or more commissures; and

coupling a prosthetic valve to the prosthetic valve support.

For some applications, the method includes removing the one or more valve support guide members following the anchoring of the prosthetic valve support at the native atrioventricular valve.

For some applications, advancing the one or more valve support guide members toward the one or more commissures includes advancing one guide member and looping the one guide member through first and second commissures of the native atrioventricular valve in a manner in which a looped portion of the guide member is disposed in a ventricle of the patient and first and second free ends of the guide member are accessible from a site outside a body of the patient.

For some applications, anchoring the one or more valve support anchors includes anchoring the one or more valve support anchors to ventricular surface of the respective commissures of the native valve.

For some applications, anchoring the one or more valve support anchors includes anchoring first and second tissue anchors to respective first and second commissures of the native valve.

For some applications:

advancing along the one or more valve support guide members the one or more valve support tissue anchors includes advancing the one or more valve support tissue anchors within a sheath, and

anchoring the one or more valve support tissue anchors includes exposing the one or more valve support anchors from within the sheath and facilitating radial expansion of one or more radially-expandable prongs of the one or more anchors.

For some applications, coupling the prosthetic valve to the prosthetic valve support includes coupling a prosthetic valve having two or more leaflets.

For some applications, the native atrioventricular valve includes a mitral valve of the patient, and coupling the prosthetic valve to the prosthetic valve support includes coupling a prosthetic valve having three leaflets.

For some applications, anchoring the prosthetic valve support includes pushing aside, at least in part, native leaflets of the valve of the patient by at least a portion of the support.

For some applications, the prosthetic valve support is coupled to one or more annulus tissue anchors, and anchoring the prosthetic valve support includes pushing the one or more annulus tissue anchors into tissue of an annulus of the native valve.

For some applications, coupling the prosthetic valve to the prosthetic valve support includes ensnaring one or more native leaflets of the native valve of the patient by a portion of the prosthetic valve.

For some applications, the one or more valve support anchors includes one or more ventricular anchors, and the method further includes advancing one or more atrial anchors to an atrial surface of the valve support, and anchoring in place the valve support in a vicinity of a respective one of the ventricular anchors.

For some applications, the method includes advancing the valve support along the one or more valve support guide members prior to the anchoring of the valve support.

For some applications, the valve support is shaped so as to define one or more holes, and advancing the valve support along the one or more valve support guide members includes threading the one or more valve support guide members through the one or more holes of the valve support and sliding the valve support along the one or more guide members.

For some applications, the method includes removing the one or more valve support guide members from a body of the patient following the anchoring of the valve support.

For some applications,

the valve support includes: <ul id="ul0009" list-style="none"><li id="ul0009-0001" num="0000"><ul id="ul0010" list-style="none"><li id="ul0010-0001" num="0176">an annular element, and</li><li id="ul0010-0002" num="0177">a generally cylindrical element having first and second ends and a cylindrical body that is disposed between the first and second ends, the first end being coupled to the annular element; and</li></ul></li></ul>

anchoring of the valve support, including anchoring the valve support in a manner in which: <ul id="ul0011" list-style="none"><li id="ul0011-0001" num="0000"><ul id="ul0012" list-style="none"><li id="ul0012-0001" num="0179">the annular element is positioned along an annulus of the native valve,</li><li id="ul0012-0002" num="0180">the second end of the cylindrical element is disposed above the annular element in an atrium of a heart of the patient, and</li><li id="ul0012-0003" num="0181">the body of the cylindrical element is disposed above the annular element.</li></ul></li></ul>

For some applications, the method includes, following the anchoring, inverting the cylindrical element to pull the second end of the cylindrical element below the annular element and into a ventricle of the heart, in a manner in which the body of the cylindrical element is disposed below the annular element and pushes aside one or more native leaflets of the valve of the patient.

For some applications:

inverting the cylindrical element includes advancing the prosthetic valve along one or more prosthetic valve guide members reversibly coupled to the cylindrical element in a vicinity of the second end thereof,

advancing the prosthetic valve includes advancing the prosthetic valve into the ventricle to pull the prosthetic valve guide members and the second end of the cylindrical element into the ventricle, and

the method further includes following the advancing of the prosthetic valve into the ventricle, pulling proximally the prosthetic valve such that a proximal portion of the valve contacts the valve support.

For some applications, pulling the prosthetic valve proximally includes ensnaring the one or more leaflets of the valve by a portion of the prosthetic valve.

For some applications, advancing the one or more valve support anchors includes:

providing a respective delivery lumen coupled at a distal end thereof to each one of the one or more anchors,

advancing each delivery lumen along a respective one of the one or more valve support guide members,

facilitating anchoring of each one of the one or more anchors to the one or more commissures by the respective delivery lumen, and

decoupling the delivery lumen from each one of the one or more valve support anchors following the anchoring of the one or more valve support anchors.

For some applications, the method includes removing the one or more valve support guide members from a body of the patient following the anchoring of each one of the one or more valve support anchors to the one or more commissures.

For some applications, the method includes advancing the prosthetic valve support along the one or more delivery lumens prior to the anchoring the support at the native atrioventricular valve.

For some applications, the valve support is shaped so as to define one or more holes, and advancing the valve support along the one or more delivery lumens includes threading the one or more delivery lumens through the one or more holes of the valve support and sliding the valve support along the one or more delivery lumens.

For some applications, the method includes removing the one or more delivery lumens from a body of the patient following the anchoring the support at the atrioventricular valve.

There is additionally provided, in accordance with some applications of the present invention, apparatus including a valve support for receiving a prosthetic valve, the valve support including:

an annular element configured to be positioned along a native annulus of a native atrioventricular valve of a patient; and

a flexible generally cylindrical element configured to be positioned in the native atrioventricular valve of the patient and to push aside native leaflets of the native valve, the cylindrical element having first and second ends and a cylindrical body that is disposed between the first and second ends, and: <ul id="ul0013" list-style="none"><li id="ul0013-0001" num="0000"><ul id="ul0014" list-style="none"><li id="ul0014-0001" num="0200">the first end of the cylindrical element is coupled to the annular element,</li><li id="ul0014-0002" num="0201">during a first period, the second end of the cylindrical element is disposed above the annular element in a manner in which the body of the cylindrical element is disposed above the annular element, and</li><li id="ul0014-0003" num="0202">the cylindrical element is invertible in a manner in which, during a second period, the second end of the cylindrical element is disposed below the annular element and the body of the cylindrical element is disposed below the annular element.</li></ul></li></ul>

For some applications, the cylindrical element includes a flexible wireframe covered by a fabric.

For some applications, the valve support is collapsible for transcatheter delivery and expandable to contact the native atrioventricular valve.

For some applications, the annular element has an upper surface and a lower surface, the lower surface is coupled to one or more annular element tissue anchors configured to puncture tissue of the native annulus of the patient.

For some applications, the one or more annular element tissue anchors includes a plurality of annular element tissue anchors positioned around the lower surface of the annular element.

For some applications, the one or more annular element tissue anchors includes a first commissural annular element tissue anchor configured to puncture tissue of the native valve at a first commissure thereof, and a second commissural annular element tissue anchor configured to puncture tissue of the native valve at a second commissure thereof.

For some applications, each anchor of the one or more annular element tissue anchors includes a distal pointed tip and one or more radially-expandable prongs, the prongs being configured to expand and facilitate anchoring of the anchor and restrict proximal motion of the annular element tissue anchor.

For some applications, the apparatus includes one or more valve support guide members configured to be delivered to one or more commissures of the native atrioventricular valve of the patient, the one or more valve support guide members are configured to facilitate advancement of the valve support toward the native valve.

For some applications, the valve support is shaped so as to define one or more holes, the one or more holes configured to facilitate slidable passage therethrough of a respective one of the one or more valve support guide members.

For some applications, the one or more valve support guide members includes one valve support guide member that is looped through first and second commissures of the atrioventricular valve in a manner in which a looped portion of the valve support guide member is disposed in a ventricle of the patient and first and second free ends of the valve support guide member are accessible from a site outside a body of the patient.

For some applications, the apparatus includes one or more valve support tissue anchors configured to be advanceable along the one or more valve support guide members and anchored to the one or more commissures of the valve.

For some applications, the one or more valve support anchors includes one or more ventricular anchors, and the apparatus further includes one or more atrial anchors, each atrial anchor being configured to be advanced toward an atrial surface of the valve support and anchor in place the valve support in a vicinity of a respective one of the ventricular anchors.

For some applications, the valve support guide members are removable from the patient following the anchoring of the valve support at the atrioventricular valve.

For some applications, the one or more valve support anchors are configured to be anchored to the one or more commissures from ventricular surfaces thereof prior to advancement of the valve support.

For some applications, the one or more valve support tissue anchors includes first and second valve support tissue anchors, the first and second valve support tissue anchors being configured to be anchored to respective first and second commissures of the atrioventricular valve of the patient.

For some applications:

the one or more valve support tissue anchors each include one or more radially-expandable prongs, and

the one or more prongs are disposed within a sheath in a compressed state prior to the anchoring and exposed from within the sheath in order to expand and facilitate anchoring of the anchor to the respective commissures.

For some applications, the apparatus includes one or more prosthetic valve guide members reversibly couplable to the cylindrical element in a vicinity of the second end of the cylindrical element, the prosthetic valve guide members being configured to facilitate advancement of the prosthetic valve therealong and toward the valve support.

For some applications, the apparatus includes the prosthetic valve, and the prosthetic valve is couplable to the valve support.

For some applications:

during the first period, the second end of the cylindrical element is disposed in an atrium of a heart of the patient and the annular element is positioned along an annulus of the native valve,

the prosthetic valve is advanceable along the one or more prosthetic valve guide members into a ventricle of the heart of the patient, and

in response to advancement of the prosthetic valve into the ventricle, the one or more prosthetic valve guide members are pulled into the ventricle and pull the second end of the cylindrical element into the ventricle to invert the cylindrical element.

For some applications, the prosthetic valve is collapsible for transcatheter delivery and expandable when exposed from within a delivery catheter.

For some applications, the prosthetic valve includes two or more prosthetic leaflets.

For some applications, the native atrioventricular valve includes a mitral valve, and the prosthetic valve includes three prosthetic leaflets.

For some applications, the prosthetic valve guide members are removable from the patient following the anchoring of the prosthetic valve at the atrioventricular valve.

For some applications, the prosthetic valve is shaped so as to define one or more snares configured to ensnare one or more native leaflets of the native valve of the patient.

There is yet additionally provided, in accordance with some applications of the present invention, a method, including:

advancing toward a native atrioventricular valve of a heart of a patient, a valve support including: <ul id="ul0015" list-style="none"><li id="ul0015-0001" num="0000"><ul id="ul0016" list-style="none"><li id="ul0016-0001" num="0233">an annular element, and</li><li id="ul0016-0002" num="0234">a generally cylindrical element having first and second ends and a cylindrical body that is disposed between the first and second ends, the first end being coupled to the annular element;</li></ul></li></ul>

anchoring the annular element to an annulus of the native atrioventricular valve, following the anchoring, the second end of the cylindrical element is disposed above the annular element in an atrium of the heart, in a manner in which the body of the cylindrical element is disposed above the annular element; and

following the anchoring, inverting the cylindrical element to pull the second end of the cylindrical element below the annular element and into a ventricle of the heart, in a manner in which the body of the cylindrical element is disposed below the annular element and pushes aside one or more native leaflets of the valve of the patient.

For some applications, anchoring the annular element to the annulus of the native atrioventricular valve includes:

advancing one or more valve support anchors that are distinct from the valve support toward one or more commissures of the heart, and

anchoring the annular element to the annulus using the one or more positioning anchors.

For some applications, the annular element is coupled to one or more annular element tissue anchors, and anchoring the annular element includes pushing the one or more annular element tissue anchors into tissue of the annulus.

For some applications:

inverting the cylindrical element includes advancing a prosthetic valve along one or more valve guide members reversibly coupled to the cylindrical element in a vicinity of the second end thereof,

advancing the prosthetic valve includes advancing the prosthetic valve into the ventricle to pull the guide members and the second end of the cylindrical element into the ventricle, and

the method further includes following the advancing of the prosthetic valve into the ventricle, pulling proximally the prosthetic valve such that a proximal portion of the valve contacts the valve support.

For some applications, pulling the prosthetic valve proximally includes ensnaring the one or more leaflets of the valve by a portion of the prosthetic valve.

There is also provided, in accordance with some applications of the present invention, apparatus including a valve support for receiving a prosthetic valve, the valve support including:

an annular element configured to be positioned along a native annulus of a native atrioventricular valve of a patient, the annular element having upper and lower surfaces; and

one or more annular element tissue anchors coupled to the lower surface of the annular element, the one or more annular element tissue anchors being configured to puncture tissue of the native annulus of the patient.

For some applications, the valve support is collapsible for transcatheter delivery and expandable to contact the native atrioventricular valve.

For some applications, the one or more annular element tissue anchors includes a plurality of annular element tissue anchors positioned around the lower surface of the annular element.

For some applications, the one or more annular element tissue anchors includes a first commissural annular element tissue anchor configured to puncture tissue of the native valve at a first commissure thereof, and a second commissural annular element tissue anchor configured to puncture tissue of the native valve at a second commissure thereof.

For some applications, each anchor of the one or more annular element tissue anchors includes a distal pointed tip and one or more radially-expandable prongs, the prongs being configured to expand and facilitate anchoring of the anchor and restrict proximal motion of the anchor.

For some applications, the apparatus includes one or more valve support guide members configured to be delivered to one or more commissures of the native atrioventricular valve of the patient, the one or more valve support guide members are configured to facilitate advancement of the valve support toward the native valve.

For some applications, the valve support is shaped so as to define one or more holes, the one or more holes configured to facilitate slidable passage therethrough of a respective one of the one or more valve support guide members.

For some applications, the one or more valve support guide members includes one valve support guide member that is looped through first and second commissures of the atrioventricular valve in a manner in which a looped portion of the valve support guide member is disposed in a ventricle of the patient and first and second free ends of the valve support guide member are accessible from a site outside a body of the patient.

For some applications, the apparatus includes one or more valve support tissue anchors that are distinct from the valve support and are configured to be advanceable along the one or more valve support guide members and anchored to the one or more commissures of the valve.

For some applications, the one or more valve support anchors includes one or more ventricular anchors, and the apparatus further includes one or more atrial anchors, each atrial anchor being configured to be advanced toward an atrial surface of the valve support and anchor in place the valve support in a vicinity of a respective one of the ventricular anchors.

For some applications, the one or more valve support guide members are removable from the patient following the anchoring of the valve support at the atrioventricular valve.

For some applications, the one or more valve support tissue anchors are configured to be anchored to the one or more commissures from ventricular surfaces thereof prior to advancement of the valve support.

For some applications, the one or more valve support tissue anchors includes first and second valve support tissue anchors, the first and second valve support tissue anchors being configured to be anchored to respective first and second commissures of the atrioventricular valve of the patient.

For some applications:

the one or more valve support tissue anchors each include one or more radially-expandable prongs, and

the one or more prongs are disposed within a sheath in a compressed state prior to the anchoring and exposed from within the sheath in order to expand and facilitate anchoring of the anchor to the respective commissures.

For some applications, the valve support further includes a flexible generally cylindrical element coupled to the annular element and configured to be positioned in the native atrioventricular valve of the patient and to push aside native leaflets of the native valve, the cylindrical element having first and second ends and a cylindrical body that is disposed between the first and second ends.

For some applications, the cylindrical element includes a flexible wireframe covered by a fabric.

For some applications, the apparatus includes one or more prosthetic valve guide members reversibly couplable to the cylindrical element in a vicinity of the second end of the cylindrical element, the prosthetic valve guide members being configured to facilitate advancement of the prosthetic valve therealong and toward the valve support.

For some applications, the apparatus includes the prosthetic valve, and the prosthetic valve is couplable to the valve support.

For some applications: <ul id="ul0017" list-style="none"><li id="ul0017-0001" num="0000"><ul id="ul0018" list-style="none"><li id="ul0018-0001" num="0269">the first end of the cylindrical element is coupled to the annular element,</li><li id="ul0018-0002" num="0270">during a first period, the second end of the cylindrical element is disposed above the annular element in a manner in which the body of the cylindrical element is disposed above the annular element, and</li><li id="ul0018-0003" num="0271">the cylindrical element is invertible in a manner in which, during a second period, the second end of the cylindrical element is disposed below the annular element and the body of the cylindrical element is disposed below the annular element.</li></ul></li></ul>

For some applications:

during the first period, the second end of the cylindrical element is disposed in an atrium of a heart of the patient,

the prosthetic valve is advanceable along the one or more prosthetic valve guide members into a ventricle of the heart of the patient, and

in response to advancement of the prosthetic valve into the ventricle, the one or more prosthetic valve guide members are pulled into the ventricle and pull the second end of the cylindrical element into the ventricle to invert the cylindrical element.

There is additionally provided, in accordance with some applications of the present invention, apparatus, including:

one or more valve support guide members configured to be delivered to one or more commissures of a native atrioventricular valve of a patient;

a prosthetic valve support configured to be advanced toward the native valve along the one or more valve support guide members and placed at the native valve;

a prosthetic valve configured to be coupled to the valve support; and

one or more sealing elements configured to facilitate sealing of an interface between the prosthetic valve support and the native valve.

For some applications, the sealing element includes a balloon disposed circumferentially around an outer surface of the prosthetic valve support.

For some applications, the sealing element includes one or more helices that are configured to facilitate sealing of commissures of the native valve with respect to the valve support by being wrapped around chordae tendineae of the native valve.

For some applications, the sealing element includes grasping elements that are configured to facilitate sealing of commissures of the native valve with respect to the valve support by grasping the commissures.

For some applications, the sealing element is configured to facilitate anchoring of the support to the native valve.

For some applications, the valve support is collapsible for transcatheter delivery and expandable to contact the native atrioventricular valve.

For some applications, the prosthetic valve includes two or more prosthetic leaflets.

For some applications, the native atrioventricular valve includes a mitral valve, and the prosthetic valve includes three prosthetic leaflets.

For some applications, the valve support guide members are removable from the patient following coupling of the prosthetic valve to the valve support.

For some applications, the valve support is shaped so as to define a distal portion which is configured to push aside, at least in part, native leaflets of the valve of the patient.

For some applications, the valve support is shaped so as to define one or more holes, the one or more holes being configured to facilitate slidable passage therethrough of a respective one of the one or more valve support guide members.

For some applications, the one or more valve support guide members includes one valve support guide member that is looped through first and second commissures of the atrioventricular valve in a manner in which a looped portion of the valve support guide member is disposed in a ventricle of the patient and first and second free ends of the valve support guide member are accessible from a site outside a body of the patient.

For some applications, the apparatus further includes:

a guide wire configured to be advanced, via the native atrioventricular valve, into a ventricle of the patient, and coupled to an inner wall of the patient's ventricle; and

a valve support guide member tube coupled to the guide wire,

and a distal portion of the valve support guide member is configured to loop through the valve support guide member tube, such that, in response to the valve support guide member being pushed distally, portions of the valve support guide member are pushed to respective commissures of the native valve.

For some applications, the prosthetic valve is shaped so as to define one or more protrusions configured to ensnare one or more native leaflets of the native valve of the patient.

For some applications, the protrusions are disposed in a sinusoidal configuration such that the protrusions conform with a saddle shape of the patient's native annulus.

For some applications, the protrusions are configured to prevent the native leaflets from interfering with a left ventricular outflow tract of the patient, by sandwiching the leaflets between the protrusions and the prosthetic valve support.

For some applications, the valve support includes:

a first end that is configured to be placed on an atrial side of a native atrioventricular valve of a patient; and

a second end that is configured, during a first period, to be disposed inside the patient's atrium, above the first end of the valve support,

the valve support being at least partially invertible in a manner in which, during a second period, the second end of the valve support is disposed at least partially inside a ventricle of the patient, below the first end of the valve support.

For some applications, the valve support includes an annular element and a generally cylindrical element coupled to the annular element, the generally cylindrical element being configured to push aside native leaflets of the native valve, and the cylindrical element has first and second ends and a cylindrical body that is disposed between the first and second ends.

For some applications, the sealing element includes a balloon disposed underneath the annular element and configured to facilitate sealing of an interface between the annular element and the native valve.

For some applications, the apparatus further includes one or more prosthetic valve guide members, the prosthetic valve guide members being configured to facilitate advancement of the prosthetic valve therealong and toward the valve support.

For some applications:

the first end of the cylindrical element is coupled to the annular element,

during a first period, the second end of the cylindrical element is disposed above the annular element in a manner in which the body of the cylindrical element is disposed above the annular element, and

the cylindrical element is invertible in a manner in which, during a second period, the second end of the cylindrical element is disposed below the annular element and the body of the cylindrical element is disposed below the annular element.

For some applications:

during the first period, the second end of the cylindrical element is disposed in an atrium of a heart of the patient and the annular element is positioned along an annulus of the native valve,

the prosthetic valve is advanceable along the one or more prosthetic valve guide members into a ventricle of the heart of the patient, and

in response to advancement of the prosthetic valve into the ventricle, the one or more prosthetic valve guide members are pulled into the ventricle and pull the second end and the body of the cylindrical element into the ventricle to invert the cylindrical element.

There is further provided, in accordance with some applications of the present invention, apparatus, including:

a prosthetic valve support configured to be advanced toward a native atrioventricular valve of a patient and placed at the native valve;

a prosthetic valve configured to be coupled to the valve support, the prosthetic valve being shaped so as to define first and second sets of one or more protrusions, each set of protrusions configured to ensnare a respective native leaflet of the native valve of the patient, the first set of protrusions being disposed within a first circumferential arc with respect to a longitudinal axis of the prosthetic valve, on a first side of a distal end of the prosthetic valve, the second set of protrusions being disposed within a second circumferential arc with respect to the longitudinal axis of the prosthetic valve, on a second side of the distal end of the prosthetic valve, the first and second sets being disposed so as to provide first and second gaps therebetween at the distal end of the prosthetic valve, at least one of the gaps having a circumferential arc of at least 20 degrees; and

one or more valve guide members configured to be delivered to one or more commissures of the native valve, and to guide the valve such that the first and second circumferential arcs are aligned with respective leaflets of the native valve and such that the first and second gaps are aligned with respective commissures of the native valve.

For some applications, the at least one of the gaps has a circumferential arc of at least 60 degrees.

For some applications, the first circumferential arc defines an angle of between 25 degrees and 90 degrees about the longitudinal axis of the prosthetic valve.

For some applications, the second circumferential arc defines an angle of between 25 degrees and 90 degrees about the longitudinal axis of the prosthetic valve.

For some applications, the first circumferential arc defines an angle of between 45 degrees and 75 degrees about the longitudinal axis of the prosthetic valve.

For some applications, the second circumferential arc defines an angle of between 45 degrees and 75 degrees about the longitudinal axis of the prosthetic valve.

There is additionally provided, in accordance with some applications of the present invention, a method, including:

determining an area defined by an annulus of a native atrioventricular valve of a patient;

selecting a prosthetic valve to be placed in the native valve by determining that the valve defines a cross-sectional area that is less than 90% of the area defined by the annulus; and

deploying the prosthetic valve at the native valve,

the selecting of the prosthetic valve facilitating sealing of the native valve with respect to the prosthetic valve by facilitating closing of leaflets of the native valve around the prosthetic valve, upon deployment of the prosthetic valve.

For some applications, selecting the prosthetic valve includes selecting a prosthetic valve having a material disposed on an outer surface thereof.

For some applications, selecting the prosthetic valve includes selecting a prosthetic valve having a material that prevents tissue growth disposed on an outer surface thereof.

For some applications, selecting the prosthetic valve includes selecting a prosthetic valve having a material that promotes tissue growth disposed on an outer surface thereof.

For some applications, selecting the prosthetic valve to be placed in the native valve includes determining that the valve defines a cross-sectional area that is less than 80% of the area defined by the annulus.

For some applications, selecting the prosthetic valve to be placed in the native valve includes determining that the valve defines a cross-sectional area that is less than 60% of the area defined by the annulus.

There is further provided, in accordance with some applications of the present invention, apparatus including:

a valve support for receiving a prosthetic valve, the valve support including: <ul id="ul0019" list-style="none"><li id="ul0019-0001" num="0000"><ul id="ul0020" list-style="none"><li id="ul0020-0001" num="0335">a first end that is configured to be placed on an atrial side of a native atrioventricular valve of a patient; and</li><li id="ul0020-0002" num="0336">a second end that is configured, during a first period, to be disposed inside the patient's atrium, above the first end of the valve support,</li><li id="ul0020-0003" num="0337">the valve support being at least partially invertible in a manner in which, during a second period, the second end of the cylindrical element is disposed at least partially inside a ventricle of the patient, below the first end of the valve support.</li></ul></li></ul>

For some applications, the valve support includes a flexible wireframe covered by a fabric.

For some applications, the valve support is collapsible for transcatheter delivery and expandable to contact the native atrioventricular valve.

For some applications, the valve support defines a surface that is an inner surface of the valve support during the first period, and an outer surface of the valve support during the second period, and the apparatus further includes a sealing material that is disposed on the surface, such that during the second period the sealing material facilitates sealing between the valve support and the native valve.

For some applications, the first end includes a coupling element configured to couple the valve support to tissue of the native valve on the atrial side of the native valve.

For some applications, the first end is shaped to define barbs that are configured to couple the valve support to tissue of the native valve on the atrial side of the native valve

For some applications, the valve support includes:

an annular element configured to be positioned along a native annulus of the native atrioventricular valve; and

a flexible generally cylindrical element configured to be positioned in the native atrioventricular valve of the patient and to push aside native leaflets of the native valve, the first end of the cylindrical element defining the first end of the valve support, and the first end of the cylindrical element being coupled to the annular element.

For some applications, the apparatus further includes one or more valve support guide members configured to be delivered to one or more commissures of the native atrioventricular valve of the patient, and the one or more valve support guide members are configured to facilitate advancement of the valve support toward the native valve.

For some applications, the valve support is shaped so as to define one or more holes, the one or more holes configured to facilitate slidable passage therethrough of a respective one of the one or more valve support guide members.

For some applications, the one or more valve support guide members includes one valve support guide member that is looped through first and second commissures of the atrioventricular valve in a manner in which a looped portion of the valve support guide member is disposed in a ventricle of the patient and first and second free ends of the valve support guide member are accessible from a site outside a body of the patient.

For some applications, the apparatus further includes:

a guide wire configured to be advanced, via the native atrioventricular valve, into a ventricle of the patient, and coupled to an inner wall of the patient's ventricle; and

a valve support guide member tube coupled to the guide wire,

and a distal portion of the valve support guide member is configured to loop through the valve support guide member tube, such that, in response to the valve support guide member being pushed distally, portions of the valve support guide member are pushed to respective commissures of the native valve.

For some applications, the apparatus further includes one or more prosthetic valve guide members reversibly couplable to the cylindrical element in a vicinity of the second end of the cylindrical element, the prosthetic valve guide members being configured to facilitate advancement of the prosthetic valve therealong and toward the valve support.

For some applications, the apparatus further includes the prosthetic valve, and the prosthetic valve is couplable to the valve support.

For some applications:

during the first period, the second end of the cylindrical element is disposed in an atrium of a heart of the patient and the annular element is positioned along an annulus of the native valve,

the prosthetic valve is advanceable along the one or more prosthetic valve guide members into a ventricle of the heart of the patient, and

in response to advancement of the prosthetic valve into the ventricle, the one or more prosthetic valve guide members are pulled into the ventricle and pull the second end of the cylindrical element into the ventricle to invert the cylindrical element.

For some applications, the apparatus further includes one or more sealing elements configured to facilitate sealing of an interface between the prosthetic valve support and the native valve.

For some applications, the sealing element includes a balloon disposed circumferentially around a surface of the prosthetic valve support.

For some applications, the sealing element includes one or more helices that are configured to facilitate sealing of commissures of the native valve with respect to the valve support by being wrapped around chordae tendineae of the native valve.

For some applications, the sealing element includes grasping elements that are configured to facilitate sealing of commissures of the native valve with respect to the valve support by grasping the commissures.

For some applications, the sealing element is configured to facilitate anchoring of the support to the native valve.

For some applications, the apparatus further includes the prosthetic valve, and the prosthetic valve is couplable to the valve support.

For some applications, the prosthetic valve is collapsible for transcatheter delivery and expandable when exposed from within a delivery catheter.

For some applications, the prosthetic valve includes two or more prosthetic leaflets.

For some applications, the native atrioventricular valve includes a mitral valve, and the prosthetic valve includes three prosthetic leaflets.

For some applications, the prosthetic valve is shaped so as to define one or more protrusions configured to ensnare one or more native leaflets of the native valve of the patient.

For some applications, the protrusions are disposed in a sinusoidal configuration such that the protrusions conform with a saddle shape of the patient's native annulus.

For some applications, the protrusions are configured to prevent the native leaflets from interfering with a left ventricular outflow tract of the patient, by sandwiching the leaflets between the protrusions and the prosthetic valve support.

There is further provided, in accordance with some applications of the present invention, apparatus, including:

a guide wire configured to be advanced into a patient's ventricle via a native atrioventricular valve of the patient, and coupled to an inner wall of the patient's ventricle;

a valve support guide member tube coupled to the guide wire;

a valve support guide member, a distal portion of the valve support guide member looping through the valve support guide member tube, such that, in response to the valve support guide member being pushed distally, portions of the valve support guide member are pushed to respective commissures of the native valve;

a prosthetic valve support configured to be advanced toward the commissures of the native valve along the valve support guide member portions; and

a prosthetic valve configured to be coupled to the valve support.

For some applications, first and second free ends of the valve support guide member are accessible from a site outside a body of the patient.

For some applications, the valve support includes:

an annular element configured to be positioned along a native annulus of the native atrioventricular valve; and

a generally cylindrical element configured to be positioned in the native atrioventricular valve of the patient and to push aside native leaflets of the native valve, the cylindrical element being coupled to the annular element, at a first end of the cylindrical element.

For some applications, the valve support is shaped so as to define one or more holes, the one or more holes configured to facilitate slidable passage therethrough of respective portions of the portions of the valve support guide member.

For some applications, the guide member is configured to facilitate advancement of the prosthetic valve therealong and toward the valve support.

For some applications, the prosthetic valve is collapsible for transcatheter delivery and expandable when exposed from within a delivery catheter.

For some applications, the prosthetic valve includes two or more prosthetic leaflets.

For some applications, the native atrioventricular valve includes a mitral valve, and the prosthetic valve includes three prosthetic leaflets.

For some applications, the guide member is removable from the patient following the coupling of the prosthetic valve to the valve support.

For some applications, the prosthetic valve is shaped so as to define one or more protrusions configured to ensnare one or more native leaflets of the native valve of the patient.

For some applications, the protrusions are disposed in a sinusoidal configuration such that the protrusions conform with a saddle shape of the patient's native annulus.

For some applications, the protrusions are configured to prevent the native leaflets from interfering with a left ventricular outflow tract of the patient, by sandwiching the leaflets between the protrusions and the prosthetic valve support.

For some applications, the apparatus further includes one or more sealing elements configured to facilitate sealing of an interface between the prosthetic valve support and the native valve.

For some applications, the sealing element includes a balloon disposed circumferentially around a surface of the prosthetic valve support.

For some applications, the sealing element includes one or more helices that are configured to facilitate sealing of commissures of the native valve with respect to the valve support by being wrapped around chordae tendineae of the native valve.

For some applications, the sealing element includes grasping elements that are configured to facilitate sealing of commissures of the native valve with respect to the valve support by grasping the commissures.

For some applications, the sealing element is configured to facilitate anchoring of the support to the native valve.

There is additionally provided, in accordance with some applications of the present invention, apparatus, including:

one or more valve guide members configured to be delivered to one or more commissures of a native atrioventricular valve of a patient;

a prosthetic valve configured to be advanced to be advanced toward the native valve along the one or more valve guide members and placed at the native valve at at least the one or more commissures; and

one or more proximally-facing grasping elements that are configured to facilitate sealing of commissures of the native valve with respect to the valve by: <ul id="ul0021" list-style="none"><li id="ul0021-0001" num="0000"><ul id="ul0022" list-style="none"><li id="ul0022-0001" num="0399">being inserted into a ventricle of the patient; and</li><li id="ul0022-0002" num="0400">being pulled proximally and being closed around tissue in a vicinity of the commissures.</li></ul></li></ul>

For some applications, the grasping elements include two surfaces that are hingedly coupled to one another, and that are configured to facilitate the sealing of the commissures of the native valve with respect to the prosthetic valve by being closed about the hinge with respect to one another.

There is further provided, in accordance with some applications of the present invention, a method, including:

advancing one or more valve support guide members toward one or more commissures of a native atrioventricular valve of a patient;

placing a prosthetic valve support at the native atrioventricular valve by advancing the valve support along the one or more valve support guide members;

coupling a prosthetic valve to the prosthetic valve support; and

facilitating sealing of an interface between the prosthetic valve support and the native valve by deploying a sealing element in a vicinity of the interface.

There is additionally provided, in accordance with some applications of the present invention, a method including:

placing a first end of a prosthetic valve support on an atrial side of a native atrioventricular valve of a patient, such that a second end of the valve support is disposed, during a first period, inside the patient's atrium, above the first end of the valve support; and

subsequent to the placing of the valve support, inverting at least a portion of the valve support such that, during a second period, the second end of the valve support is disposed at least partially inside a ventricle of the patient, below the first end of the valve support.

There is additionally provided, in accordance with some applications of the present invention, a method, including:

advancing a guide wire, via a native atrioventricular valve, into a ventricle of the patient, a valve support guide member tube being coupled to the guide wire;

coupling a distal end of the guide wire to an inner wall of the patient's ventricle; and

causing portions of a valve support guide member to be pushed to respective commissures of the native valve, by pushing the guide member distally, a distal portion of the valve support guide member looping through the valve support guide member tube;

advancing a prosthetic valve support toward the commissures of the native valve along the valve support guide member portions; and

coupling a prosthetic valve to the valve support.

There is further provided, in accordance with some applications of the present invention, a method, including:

advancing one or more valve guide members toward one or more commissures of a native atrioventricular valve of a patient;

placing a prosthetic valve at the native atrioventricular valve by advancing the valve along the one or more valve guide members; and

facilitating sealing of commissures of the native valve with respect to the valve by: <ul id="ul0023" list-style="none"><li id="ul0023-0001" num="0000"><ul id="ul0024" list-style="none"><li id="ul0024-0001" num="0420">inserting into a ventricle of the patient one or more grasping elements that are coupled to the prosthetic valve;</li><li id="ul0024-0002" num="0421">pulling the grasping elements proximally; and</li><li id="ul0024-0003" num="0422">closing the grasping elements around tissue in a vicinity of the commissures.</li></ul></li></ul>

The present invention will be more fully understood from the following detailed description of embodiments thereof, taken together with the drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

<figref idref="DRAWINGS">FIGS. 1A-B</figref> are schematic illustrations of advancement of one or more guide members toward respective commissures of a mitral valve, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 1C-D</figref> are schematic illustrations of the advancement and deployment of commissural anchors via the guide members, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 2A-D</figref> are schematic illustrations of the advancement of a prosthetic valve support toward a native atrioventricular valve of a patient, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 2E-F</figref> are schematic illustrations of locking of the prosthetic valve support at the native valve, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 2G-K</figref> are schematic illustrations of the advancement of a prosthetic valve and the coupling of the prosthetic valve to the valve support, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 3A-B</figref> are schematic illustrations of the advancement of a prosthetic valve support toward a native atrioventricular valve of a patient, the valve support including a sealing balloon, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 3C-D</figref> are schematic illustrations of locking of the prosthetic valve support at the native valve, the valve support including the sealing balloon, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 4A-C</figref> are schematic illustrations of a valve support being used with commissural helices that facilitate anchoring and/or sealing of the valve support, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 5A-D</figref> are schematic illustrations of grasping elements being used to anchor and/or provide sealing of a prosthetic valve, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 6A-B</figref> are schematic illustrations of a prosthetic valve that includes a sealing material, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 7A-F</figref> are schematic illustrations of a guide wire delivery system, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 8A-C</figref> are schematic illustrations of a valve support that has a cylindrical element that is invertible, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 9A-D</figref> are schematic illustrations of the advancement of an invertible prosthetic valve support toward a native atrioventricular valve of a patient, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIG. 9E</figref> is a schematic illustration of inversion of the invertible prosthetic valve support at the native valve, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 9F-H</figref> are schematic illustrations of the advancement of a prosthetic valve and the coupling of the prosthetic valve to the invertible valve support, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIG. 10</figref> is a schematic illustration of a prosthetic valve, the cross-sectional area of which is smaller than the area defined by the patient's native valve annulus, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 11A-D</figref> are schematic illustrations of a prosthetic valve that defines protrusions from portions of the distal end of the valve, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 12A-C</figref> are schematic illustrations of a prosthetic valve that defines distal protrusions that are disposed sinusoidally around the circumference of the valve, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 13A-E</figref> are schematic illustrations of respective configurations of a frame of a prosthetic valve, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 14A-D</figref> are schematic illustrations of respective configurations of a prosthetic valve support, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 15A-E</figref> are schematic illustrations of respective steps of a procedure for deploying a prosthetic valve, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 16A-H</figref> are schematic illustrations of respective steps of an alternative procedure for deploying a prosthetic valve, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 17A-C</figref> are schematic illustrations of leaflets of a prosthetic valve, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 18A-B</figref> are schematic illustrations of a valve support coupled to a plurality of tissue anchors, in accordance with some applications of the present invention;

<figref idref="DRAWINGS">FIGS. 19A-D</figref> are schematic illustrations of the valve support of <figref idref="DRAWINGS">FIGS. 18A-B</figref> being implanted in the native valve of the patient and facilitating implantation of a prosthetic valve, in accordance with some applications of the present invention; and

<figref idref="DRAWINGS">FIGS. 20A-B</figref> are schematic illustrations of a prosthetic valve and a prosthetic valve support deployed, respectively, at a tricuspid valve, and at an aortic valve, in accordance with some applications of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Reference is now made to <figref idref="DRAWINGS">FIGS. 1A-B</figref>, which are schematic illustrations of a system <b>20</b> for replacing an atrioventricular valve <b>5</b> of a patient comprising one or more guide members <b>21</b><i>a </i>and <b>21</b><i>b </i>which are advanced toward first and second commissures <b>8</b> and <b>10</b> of valve <b>5</b> of a heart <b>2</b> of the patient, in accordance with some applications of the present invention. For some applications, guide members <b>21</b><i>a </i>and <b>21</b><i>b </i>comprise distinct guide members. Alternatively (as shown in <figref idref="DRAWINGS">FIGS. 7A-F</figref>), only one guide member is looped through commissures <b>8</b> and <b>10</b> in a manner in which the guide member defines a looped portion between commissures <b>8</b> and <b>10</b> (i.e., a portion of the guide member that is disposed in a ventricle <b>6</b> of heart <b>2</b>), and first and second free ends which are disposed and accessible at a site outside the body of the patient. For such applications, the guide member defines portions <b>21</b><i>a </i>and <b>21</b><i>b. </i>

It is noted that for applications in which valve <b>5</b> is the patient's mitral valve, first and second commissures <b>8</b> and <b>10</b> are the anterior and posterior commissures. For applications in which valve <b>5</b> is the patient's tricuspid valve (which includes three commissures), the first and second commissures are typically the anterior and posterior commissures of the tricuspid valve.

For some applications, guide members <b>21</b><i>a </i>and <b>21</b><i>b </i>comprise guide wires having a diameter of 0.035 inches.

The transcatheter procedure typically begins with the advancing of a semi-rigid guide wire into a right atrium <b>4</b> of the patient. The semi-rigid guide wire provides a guide for the subsequent advancement of a sheath <b>25</b> therealong and into the right atrium. Once sheath <b>25</b> has entered the right atrium, the semi-rigid guide wire is retracted from the patient's body. Sheath <b>25</b> typically comprises a 13-20 F sheath, although the size may be selected as appropriate for a given patient. Sheath <b>25</b> is advanced through vasculature into the right atrium using a suitable point of origin typically determined for a given patient. For example: <ul id="ul0025" list-style="none"><li id="ul0025-0001" num="0000"><ul id="ul0026" list-style="none"><li id="ul0026-0001" num="0454">sheath <b>25</b> may be introduced into the femoral vein of the patient, through an inferior vena cava, into the right atrium, and into the left atrium transseptally, typically through the fossa ovalis;</li><li id="ul0026-0002" num="0455">sheath <b>25</b> may be introduced into the basilic vein, through the subclavian vein to the superior vena cava, into the right atrium, and into the left atrium transseptally, typically through the fossa ovalis; or</li><li id="ul0026-0003" num="0456">sheath <b>25</b> may be introduced into the external jugular vein, through the subclavian vein to the superior vena cava, into the right atrium, and into the left atrium transseptally, typically through the fossa ovalis.</li></ul></li></ul>

In some applications of the present invention, sheath <b>25</b> is advanced through the inferior vena cava of the patient and into the right atrium using a suitable point of origin typically determined for a given patient.

Sheath <b>25</b> is advanced distally until sheath <b>25</b> reaches the interatrial septum. For some applications, a resilient needle and a dilator (not shown) are advanced through the sheath and into the heart. In order to advance the sheath transseptally into the left atrium, the dilator is advanced to the septum, and the needle is pushed from within the dilator and is allowed to puncture the septum to create an opening that facilitates passage of the dilator and subsequently the sheath therethrough and into the left atrium. The dilator is passed through the hole in the septum created by the needle. Typically, the dilator is shaped to define a hollow shaft for passage along the needle, and the hollow shaft is shaped to define a tapered distal end. This tapered distal end is first advanced through the hole created by the needle. The hole is enlarged when the gradually increasing diameter of the distal end of the dilator is pushed through the hole in the septum.

The advancement of sheath <b>25</b> through the septum and into the left atrium is followed by the extraction of the dilator and the needle from within sheath <b>25</b>.

<figref idref="DRAWINGS">FIGS. 1C-D</figref> and <b>2</b>A-B show advancement of one or more tissue anchors <b>30</b><i>a </i>and <b>30</b><i>b </i>along guide members <b>21</b><i>a </i>and <b>21</b><i>b</i>, respectively. Anchors <b>30</b><i>a </i>and <b>30</b><i>b </i>comprise a flexible, biocompatible material (e.g., nitinol) and comprise one or more (e.g., a plurality of) radially-expandable prongs <b>32</b> (e.g., barbs). Each anchor <b>30</b><i>a </i>and <b>30</b><i>b </i>is reversibly coupled to a respective delivery lumen <b>27</b><i>a </i>and <b>27</b><i>b</i>. Each delivery lumen <b>27</b> slides around a respective guide member <b>21</b>. A respective surrounding sheath <b>26</b><i>a </i>and <b>26</b><i>b </i>surrounds each delivery lumen <b>27</b><i>a </i>and <b>27</b><i>b </i>and around anchors <b>30</b><i>a </i>and <b>30</b><i>b </i>at least in part in order to compress and prevent expansion of prongs <b>32</b> of tissue anchors <b>30</b><i>a </i>and <b>30</b><i>b. </i>

As shown in <figref idref="DRAWINGS">FIG. 1D</figref>, the distal ends of lumens <b>27</b><i>a </i>and <b>27</b><i>b </i>are reversibly coupled to ribbed crimping structures <b>34</b>. As described hereinbelow, anchors <b>30</b><i>a </i>and <b>30</b><i>b </i>are anchored to ventricular surfaces of commissures <b>8</b> and <b>10</b>. Following the anchoring, ribbed crimping structures <b>34</b> extend from anchors <b>30</b><i>a </i>and <b>30</b><i>b </i>through commissures <b>8</b> and <b>10</b>, respectively, and toward the atrial surfaces of commissures <b>8</b> and <b>10</b>. Ribbed crimping structures <b>34</b> are configured to facilitate anchoring of a valve support (described hereinbelow) to the atrial surfaces of commissures <b>8</b> and <b>10</b>.

Anchors <b>30</b><i>a </i>and <b>30</b><i>b</i>, ribbed crimping structures <b>34</b>, and the distal ends of surrounding sheaths <b>26</b><i>a </i>and <b>26</b><i>b </i>are advanced into ventricle <b>6</b>. Subsequently, anchors <b>30</b><i>a </i>and <b>30</b><i>b </i>are pushed distally from within sheaths <b>26</b><i>a </i>and <b>26</b><i>b</i>, (or sheaths <b>26</b><i>a </i>and <b>26</b><i>b </i>are pulled proximally with respect to anchors <b>30</b><i>a </i>and <b>30</b><i>b</i>) to expose anchors <b>30</b><i>a </i>and <b>30</b><i>b</i>. As anchors <b>30</b><i>a </i>and <b>30</b><i>b </i>are exposed from within sheaths <b>26</b><i>a </i>and <b>26</b><i>b</i>, prongs <b>32</b> are free to expand, as shown in <figref idref="DRAWINGS">FIG. 1D</figref>. Prongs <b>32</b> expand such that anchors <b>30</b><i>a </i>and <b>30</b><i>b </i>assume a flower shape. Prongs <b>32</b>, collectively in their expanded state, create a larger surface area to engage tissue than in their compressed states. Following the exposing of anchors <b>30</b><i>a </i>and <b>30</b><i>b</i>, sheaths <b>26</b><i>a </i>and <b>26</b><i>b </i>are extracted.

As shown in <figref idref="DRAWINGS">FIG. 2B</figref>, lumens <b>27</b><i>a </i>and <b>27</b><i>b </i>are pulled proximally so that prongs <b>32</b> of anchors <b>30</b><i>a </i>and <b>30</b><i>b </i>engage respective ventricular surface of commissures <b>8</b> and <b>10</b>. Prongs <b>32</b> create a large surface area which restricts proximal motion of anchors <b>30</b><i>a </i>and <b>30</b><i>b </i>from commissures <b>8</b> and <b>10</b>, respectively.

For some applications, following the anchoring of anchors <b>30</b><i>a </i>and <b>30</b><i>b </i>to commissures <b>8</b> and <b>10</b>, respectively, guide members <b>21</b><i>a </i>and <b>21</b><i>b </i>are removed from the body of the patient.

Reference is now made to <figref idref="DRAWINGS">FIGS. 2C-F</figref>, which are schematic illustrations of the advancement of a prosthetic valve support <b>40</b> along lumens <b>27</b><i>a </i>and <b>27</b><i>b</i>, in accordance with some applications of the present invention. In such a manner, lumens <b>27</b><i>a </i>and <b>27</b><i>b </i>function as valve support guide members. Support <b>40</b> comprises a collapsible skirt having a proximal annular element <b>44</b> and a distal cylindrical element <b>42</b>. Support <b>40</b> is configured to assume a collapsed state (e.g., surrounded by a sheath or overtube <b>50</b> shown in <figref idref="DRAWINGS">FIG. 2C</figref>) for minimally-invasive delivery to the diseased native valve, such as by percutaneous or transluminal delivery using one or more catheters. <figref idref="DRAWINGS">FIG. 2C</figref> and the other figures show support <b>40</b> in an expanded state after delivery in right atrium <b>4</b> and advancement toward the native valve. As shown in <figref idref="DRAWINGS">FIG. 2D</figref>, support <b>40</b> is shaped so as to define one or more (e.g., two, as shown in View A) holes <b>46</b><i>a </i>and <b>46</b><i>b </i>for slidable advancement of support <b>40</b> along lumens <b>27</b><i>a </i>and <b>27</b><i>b</i>, respectively. That is, prior to introduction of support <b>40</b> into the body of the patient, lumens <b>27</b><i>a </i>and <b>27</b><i>b </i>are threaded through holes <b>46</b><i>a </i>and <b>46</b><i>b</i>, respectively, and support <b>40</b> is slid along lumens <b>27</b><i>a </i>and <b>27</b><i>b</i>. Support <b>40</b> is slid by pushing elements <b>52</b><i>a </i>and <b>52</b><i>b </i>which surround delivery lumens <b>27</b><i>a </i>and <b>27</b><i>b</i>, respectively.

It is to be noted that support <b>40</b> is slid along lumens <b>27</b><i>a </i>and <b>27</b><i>b </i>by way of illustration and not limitation. That is, for some applications, following the anchoring of anchors <b>30</b><i>a </i>and <b>30</b><i>b </i>to commissures <b>8</b> and <b>10</b>, respectively, guide members <b>21</b><i>a </i>and <b>21</b><i>b </i>are not removed from the body of the patient, but rather lumens <b>27</b><i>a </i>and <b>27</b><i>b </i>are removed (e.g., by being decoupled from crimping structures <b>34</b>) leaving behind anchors <b>30</b><i>a </i>and <b>30</b><i>b </i>and guide members <b>21</b><i>a </i>and <b>21</b><i>b</i>. Guide members <b>21</b><i>a </i>and <b>21</b><i>b </i>may then be threaded through holes <b>46</b><i>a </i>and <b>46</b><i>b</i>, respectively, and support <b>40</b> is slid along guide members <b>21</b><i>a </i>and <b>21</b><i>b</i>. In such a manner, guide members <b>21</b><i>a </i>and <b>21</b><i>b </i>function as valve support guide members.

Support <b>40</b> comprises a collapsible flexible support frame <b>48</b>, which is at least partially covered by a covering <b>49</b>. Support <b>40</b> is configured to be placed at native valve <b>5</b>, such that cylindrical element <b>42</b> passes through the orifice of the native valve and extends towards, and, typically partially into, ventricle <b>6</b> (as shown in <figref idref="DRAWINGS">FIG. 2E</figref>). Cylindrical element <b>42</b> typically pushes aside and presses against native leaflets of native valve <b>5</b> at least in part, which are left in place during and after implantation of the prosthetic valve. Annular element <b>44</b> is configured to be placed around a native annulus <b>11</b> of the native valve, and to extend at least partially into an atrium <b>4</b> such that annular element <b>44</b> rests against the native annulus. Annular element <b>44</b> is typically too large to pass through the annulus, and may, for example, have an outer diameter of between 30 and 60 mm.

For some applications, collapsible support frame <b>48</b> comprises a stent, which comprises a plurality of struts. The struts may comprise, for example, a metal such as nitinol or stainless steel. For some applications, frame <b>48</b> comprises a flexible metal, e.g., nitinol, which facilitates compression of support <b>40</b> within a delivery sheath or overtube <b>50</b>. For some applications, covering <b>49</b> comprises a fabric, such as a woven fabric, e.g., Dacron. Covering <b>49</b> is typically configured to cover at least a portion of cylindrical element <b>42</b>, and at least a portion of annular element <b>44</b>. The covering may comprise a single piece, or a plurality of pieces sewn together.

As shown in <figref idref="DRAWINGS">FIG. 2D</figref>, pushing elements <b>52</b><i>a </i>and <b>52</b><i>b </i>are each coupled to locking crimping elements <b>64</b><i>a </i>and <b>64</b><i>b</i>, respectively. Locking crimping elements <b>64</b><i>a </i>and <b>64</b><i>b </i>are disposed adjacently, proximally to holes <b>46</b><i>a </i>and <b>46</b><i>b </i>respectively of valve support <b>40</b>. These techniques enable the surgeon to readily bring crimping elements <b>64</b><i>a </i>and <b>64</b><i>b </i>to the appropriate sites along annular element <b>44</b>, without the need for excessive imaging, such as fluoroscopy.

<figref idref="DRAWINGS">FIG. 2E</figref> shows valve support <b>40</b> prior to implantation at annulus <b>11</b>. As shown, ribbed crimping structures <b>34</b> project away from anchors <b>30</b><i>a </i>and <b>30</b><i>b</i>, through commissures <b>8</b> and <b>10</b>, and toward atrium <b>4</b>. Valve support <b>40</b> is advanced along lumens <b>27</b><i>a </i>and <b>27</b><i>b </i>toward structures <b>34</b> by being pushed by pushing elements <b>52</b><i>a </i>and <b>52</b><i>b </i>and locking crimping elements <b>64</b><i>a </i>and <b>64</b><i>b. </i>

In <figref idref="DRAWINGS">FIG. 2F</figref>, valve support <b>40</b> is further pushed by pushing elements <b>52</b><i>a </i>and <b>52</b><i>b </i>and locking crimping elements <b>64</b><i>a </i>and <b>64</b><i>b </i>such holes <b>46</b><i>a </i>and <b>46</b><i>b </i>of support <b>40</b> advance around ribbed crimping structures <b>34</b>. As holes <b>46</b><i>a </i>and <b>46</b><i>b </i>are advanced around ribbed crimping structures <b>34</b>, locking crimping elements <b>64</b><i>a </i>and <b>64</b><i>b </i>advance over and surround ribbed crimping elements <b>34</b> to lock in place valve support <b>40</b> from an atrial surface of valve <b>5</b>.

Responsively to the placement of valve support <b>40</b> at native valve <b>5</b>, cylindrical element <b>42</b> is positioned partially within ventricle <b>6</b> and native leaflets <b>12</b> and <b>14</b> of native valve <b>5</b> are pushed aside.

As shown in section A-A, ribbed crimping structures <b>34</b> are shaped so as to define a plurality of male couplings. Locking crimping elements <b>64</b><i>a </i>and <b>64</b><i>b </i>each comprise a cylindrical element having an inner lumen that is shaped so as to surround a respective ribbed crimping structure <b>34</b>. Each inner lumen of locking crimping elements <b>64</b><i>a </i>and <b>64</b><i>b </i>is shaped so as to define female couplings to receive the male couplings of ribbed crimping structure <b>34</b>. The female couplings of locking crimping element <b>64</b> are directioned such that they facilitate distal advancement of locking crimping element <b>64</b> while restricting proximal advancement of locking crimping element <b>64</b>. When the female couplings of locking crimping element <b>64</b> receive the male couplings of ribbed crimping structure <b>34</b>, valve support <b>40</b> is locked in place from an atrial surface of valve <b>5</b>. It is to be noted that for some applications, ribbed crimping elements <b>34</b> comprise female couplings, and locking crimping elements <b>64</b> comprise male couplings.

Reference is now made to <figref idref="DRAWINGS">FIGS. 2G-K</figref> which are schematic illustrations of the coupling of a prosthetic atrioventricular valve <b>80</b> to valve support <b>40</b>, in accordance with some applications of the present invention. Support <b>40</b> receives the prosthetic valve and functions as a docking station. Thus, the docking station is a coupling element that provides coupling between two other elements (in this case, between annulus <b>11</b> and the prosthetic valve.)

Following the placement of support <b>40</b> at annulus <b>11</b>, pushing elements <b>52</b><i>a </i>and <b>52</b><i>b </i>and sheath or overtube <b>50</b> are removed from the body of the patient, leaving behind lumens <b>27</b><i>a </i>and <b>27</b><i>b</i>, as shown in <figref idref="DRAWINGS">FIG. 2G</figref>.

As shown in <figref idref="DRAWINGS">FIG. 2G</figref>, a guide wire <b>72</b> is advanced toward ventricle <b>6</b> and facilitates the advancement of an overtube <b>70</b> through sheath <b>25</b> and the positioning of a distal end of overtube <b>70</b> within ventricle <b>6</b>. Overtube <b>70</b> facilitates the advancement of prosthetic valve <b>80</b> in a compressed state, toward valve support <b>40</b>.

<figref idref="DRAWINGS">FIG. 2H</figref> shows partial deployment of valve <b>80</b> within ventricle <b>6</b> of heart <b>2</b>. Valve <b>80</b> is shown comprising an expandable frame <b>79</b> comprising a plurality of stent struts by way of illustration and not limitation. The wireframe of valve <b>80</b> comprises a flexible metal, e.g., nitinol or stainless steel. It is to be noted that the wireframe of valve <b>80</b> is covered by a covering (not shown for clarity of illustration) comprising a braided mesh or in a fabric such as a woven fabric, e.g., Dacron. The covering is typically configured to cover at least a portion of the frame. The covering may comprise a single piece, or a plurality of pieces sewn together. Expandable frame <b>79</b> is typically self-expandable, although the scope of the present invention includes using a prosthetic valve that includes a balloon expandable frame, mutatis mutandis.

Following the partial deployment of valve <b>80</b> in ventricle <b>6</b>, overtube <b>70</b> is pulled proximally to pull valve <b>80</b> proximally such that cylindrical element <b>42</b> and/or annular element <b>44</b> of valve support <b>40</b> surrounds a proximal portion of prosthetic valve <b>80</b>. Valve <b>80</b> has a tendency to expand such that valve <b>80</b> is held in place with respect to valve support <b>40</b> responsively to radial forces acted upon valve support <b>40</b> by prosthetic valve <b>80</b>.

Valve <b>80</b> comprises a plurality of distal protrusions <b>84</b> (e.g., snares). When valve <b>80</b> is pulled proximally, as described hereinabove, protrusions <b>84</b> ensnare and engage the native leaflets of the atrioventricular valve. By the ensnaring of the native leaflets, protrusions <b>84</b> sandwich the native valve between protrusions <b>84</b> and prosthetic valve support <b>40</b>. Such ensnaring helps further anchor prosthetic valve <b>80</b> to the native atrioventricular valve. The scope of the present invention includes using any sort of protrusions (e.g., hooks) that protrude from the distal end of expandable frame <b>79</b> of prosthetic valve <b>80</b> and that are configured such that the native valve is sandwiched between the protrusions and valve support <b>40</b>. Typically, the protrusions cause sandwiching of the native valve leaflets, such that the leaflets do not interfere with the left ventricular outflow tract (LVOT).

For some applications, protrusions <b>84</b> are such as to (a) prevent proximal migration of the valve into the patient's atrium, while (b) allowing movement of the native leaflets with respect to the frame of the prosthetic valve. For example, the protrusions may have the aforementioned functionalities by having lengths of less than 5 mm, and/or by a total width of each set of protrusions corresponding to respective leaflets of the native valve being less than 5 mm. For example, the valve may include a single protrusion corresponding to each leaflet of the native valve, the width of each of the single protrusions being less than 1 mm. Thus, the valve may be stopped from proximally migrating into the atrium, by the protrusions preventing the distal end of the valve from migrating further proximally than edges of native leaflets of the valve. Furthermore, the protrusions may allow movement of the native leaflets with respect to the frame of the prosthetic valve by not generally squeezing the native leaflets between the protrusions and the frame of the valve. For some applications, by allowing movement of the native leaflets with respect to the frame of the prosthetic valve, sealing of the native leaflets against the outer surface of the frame of the prosthetic valve is facilitated, in accordance with the techniques described hereinbelow with reference to <figref idref="DRAWINGS">FIG. 10</figref>. Typically, valve support <b>40</b> prevents the valve from migrating distally into the patient's ventricle.

For some applications, during the procedure, the prosthetic valve is pulled back proximally with respect to valve support, as described hereinabove. The prosthetic valve is pulled back to a position with respect to valve support that is such that protrusions <b>84</b> prevent the native leaflets from interfering with the LVOT, by sandwiching the native leaflets between the protrusions and the valve support, and/or by anchoring ends of the native leaflets as described hereinabove. The prosthetic valve is then deployed at this position.

For some applications, protrusions are disposed on the valve on the sides of the valve that are adjacent to the anterior and posterior leaflets of the native valve, and the valve does not includes protrusions on the portions of the valve that are adjacent to the commissures of the native valve, as described with reference to <figref idref="DRAWINGS">FIGS. 11A-D</figref>. For some applications, the protrusions are disposed in a sinusoidal configuration in order to conform with the saddle shape of the native valve, as described hereinbelow with reference to <figref idref="DRAWINGS">FIGS. 12A-C</figref>.

Additionally, as shown in <figref idref="DRAWINGS">FIG. 2J</figref>, valve <b>80</b> comprises one or more (e.g., a plurality, as shown) coupling elements <b>81</b> at the proximal end of valve <b>80</b>. Overtube <b>70</b>, which facilitates the advancement of prosthetic valve <b>80</b>, is reversibly coupled to valve <b>80</b>, via coupling elements <b>81</b>.

Prosthetic valve <b>80</b> is configured for implantation in and/or at least partial replacement of a native atrioventricular valve <b>5</b> of the patient, such as a native mitral valve or a native tricuspid valve. Prosthetic valve <b>80</b> is configured to assume a collapsed state for minimally-invasive delivery to the diseased native valve, such as by percutaneous or transluminal delivery using one or more catheters. <figref idref="DRAWINGS">FIG. 2J</figref> shows prosthetic valve <b>80</b> in an expanded state after delivery to the native valve.

Reference is now made to <figref idref="DRAWINGS">FIG. 2K</figref> which shows a bird's-eye view of valve <b>80</b>. Prosthetic valve <b>80</b> further comprises a plurality of valve leaflets <b>82</b>, which may be artificial or tissue-based. The leaflets are typically coupled to an inner surface of the valve prosthesis. Leaflets <b>82</b> are coupled, e.g., sewn, to expandable frame <b>79</b> and/or to the covering. For applications in which the prosthetic valve is configured to be implanted at the native mitral valve, the prosthetic valve typically comprises three leaflets <b>82</b><i>a</i>, <b>82</b><i>b</i>, and <b>82</b><i>c</i>, as shown in <figref idref="DRAWINGS">FIG. 2K</figref>.

Reference is now made to <figref idref="DRAWINGS">FIGS. 3A-D</figref>, which are schematic illustrations of the advancement of prosthetic valve support <b>40</b> toward native atrioventricular valve <b>5</b> of a patient, the valve support including a sealing balloon <b>90</b>, in accordance with some applications of the present invention. The steps shown in <figref idref="DRAWINGS">FIGS. 3A-C</figref> are generally similar to those shown in <figref idref="DRAWINGS">FIGS. 2C-F</figref>. For some applications, sealing balloon <b>40</b> is disposed on the valve-facing, lower side of annular element <b>44</b> of the prosthetic valve support. <figref idref="DRAWINGS">FIG. 3D</figref> shows valve support <b>40</b>, the valve support having been implanted at annulus <b>11</b>. Typically, at this stage, balloon <b>40</b> is inflated, as shown in the transition from <figref idref="DRAWINGS">FIG. 3C</figref> to <figref idref="DRAWINGS">FIG. 3D</figref>. The balloon is inflated via an inflation lumen <b>92</b>, shown in <figref idref="DRAWINGS">FIG. 3C</figref>, for example. For some applications, the balloon seals the interface between the prosthetic valve support and native annulus <b>11</b>, thereby reducing retrograde blood flow from ventricle <b>6</b> into atrium <b>4</b>, relative to retrograde blood flow in the absence of a sealing balloon. For some applications, the balloon is inflated prior to the placement of the prosthetic support at annulus <b>11</b>.

Reference is now made to <figref idref="DRAWINGS">FIGS. 4A-C</figref>, which are schematic illustrations of prosthetic valve support <b>40</b> being used with commissural helices <b>100</b><i>a </i>and <b>100</b><i>b </i>that facilitate anchoring and/or sealing of the valve support, in accordance with some applications of the present invention. For some applications, commissural helices are used as an alternative or in addition to anchors <b>30</b><i>a </i>and <b>30</b><i>b </i>and/or other anchoring elements described herein, in order to facilitate the anchoring of valve support <b>40</b>.

Commissural helices <b>100</b><i>a </i>and <b>100</b><i>b </i>are typically placed at commissures <b>8</b> and <b>10</b> in a generally similar technique to that described with reference to anchors <b>30</b><i>a </i>and <b>30</b><i>b</i>. Typically, each helix <b>30</b><i>a </i>and <b>30</b><i>b </i>is reversibly coupled to a respective delivery lumen <b>27</b><i>a </i>and <b>27</b><i>b</i>. As described above, each delivery lumen <b>27</b> slides around a respective guide member <b>21</b>, and a respective surrounding sheath <b>26</b><i>a </i>and <b>26</b><i>b </i>surrounds each delivery lumen <b>27</b><i>a </i>and <b>27</b><i>b. </i>

Commissural helices <b>100</b><i>a </i>and <b>100</b><i>b </i>(optionally, ribbed crimping structures <b>34</b>), and the distal ends of surrounding sheaths <b>26</b><i>a </i>and <b>26</b><i>b </i>are advanced into ventricle <b>6</b>. The helices are pushed out of the distal ends of surrounding sheaths <b>26</b><i>a </i>and <b>26</b><i>b. </i>

Subsequently, the helices are rotated proximally such that the helices wrap around at least some chordae tendineae <b>102</b> of the patient. Following the advancement of the helices out of sheaths <b>26</b><i>a </i>and <b>26</b><i>b</i>, the sheaths are extracted. For some applications the helices are conical helices (as shown), and the wider end of the conical helix is disposed at the proximal end of the helix.

Subsequent to the placement of commissural helices <b>100</b><i>a </i>and <b>100</b><i>b </i>around the chordae tendineae, prosthetic valve support <b>40</b> is placed at annulus <b>11</b>, in accordance with the techniques described hereinabove, and as shown in <figref idref="DRAWINGS">FIG. 4B</figref>. Subsequently, prosthetic valve <b>80</b> is coupled to the prosthetic valve support, in accordance with the techniques described hereinabove, and as shown in <figref idref="DRAWINGS">FIG. 4C</figref>.

Typically, commissural helices <b>100</b><i>a </i>and <b>100</b><i>b </i>facilitate sealing of native commissures <b>8</b> and <b>10</b>, thereby reducing retrograde blood flow via the commissures, relative to retrograde blood flow in the absence of the helices. Further typically, the sealing of the native commissures facilitates anchoring of the prosthetic valve support to native valve <b>5</b>.

Reference is now made to <figref idref="DRAWINGS">FIGS. 5A-D</figref>, which are schematic illustrations of grasping elements <b>106</b><i>a </i>and <b>106</b><i>b </i>being used to anchor prosthetic valve <b>80</b>, in accordance with some applications of the present invention. For some applications, guide members <b>21</b><i>a </i>and <b>21</b><i>b </i>are advanced toward first and second commissures <b>8</b> and <b>10</b> of valve <b>5</b> of the patient, as described hereinabove. Grasping elements <b>106</b><i>a </i>and <b>106</b><i>b </i>are reversibly coupled to distal ends of delivery lumen <b>27</b><i>a </i>and <b>27</b><i>b</i>, the delivery lumens being advanced over respective guide members, as described hereinabove. For some applications, the guiding members and the grasping elements are advanced toward the patient's commissures via surrounding sheaths <b>26</b><i>a </i>and <b>26</b><i>b</i>, the surrounding sheaths being generally as described hereinabove. The grasping elements are typically placed distally to the commissures in a proximally-facing configuration, as shown in <figref idref="DRAWINGS">FIG. 5A</figref>. For example, as shown, the grasping elements may be configured to be proximally facing due to the coupling of the grasping elements to the guide members.

Subsequent to the placement of grasping elements <b>106</b><i>a </i>and <b>106</b><i>b </i>distally to native commissures <b>8</b> and <b>10</b>, prosthetic valve <b>80</b> is advanced toward native valve <b>5</b>, as shown in <figref idref="DRAWINGS">FIG. 5B</figref>. For example, the prosthetic valve may be advanced over delivery lumens <b>27</b><i>a </i>and <b>27</b><i>b</i>, as shown. The prosthetic valve is placed at the native valve and, subsequently, the grasping elements are retracted proximally toward commissures <b>8</b> and <b>10</b>, as shown in the transition from <figref idref="DRAWINGS">FIG. 5B</figref> to <figref idref="DRAWINGS">FIG. 5C</figref>. For some applications, the grasping elements are coupled to valve <b>80</b> via coupling tubes <b>107</b><i>a </i>and <b>107</b><i>b</i>, the coupling tubes being coupled to the sides of the valve, as shown. The grasping elements are closed such that the native commissures are grasped and sealed by the grasping elements, as shown in <figref idref="DRAWINGS">FIG. 5D</figref>. Typically, the grasping elements define two surfaces that are hingedly coupled to each other. For example, the grasping elements may include forceps, as shown. The grasping elements are closed by closing the surfaces about the hinge, with respect to one another.

Typically, grasping elements <b>106</b><i>a </i>and <b>106</b><i>b </i>facilitate sealing of native commissures <b>8</b> and <b>10</b>, thereby reducing retrograde blood flow via the commissures, relative to retrograde blood flow in the absence of the grasping elements. Further typically, the sealing of the native commissures facilitates anchoring of the prosthetic valve to native valve <b>5</b>.

Although not shown, for some applications, prosthetic valve support <b>40</b> is used in addition to grasping elements <b>106</b><i>a </i>and <b>106</b><i>b</i>, in order to anchor prosthetic valve <b>80</b> to native valve <b>5</b>. For some applications, the grasping elements are used to anchor and/or provide sealing for prosthetic valve support <b>40</b> (instead of, or in addition to, being used to anchor prosthetic valve <b>80</b>, as shown). For such applications, generally similar techniques are used to those described with respect to the use of the grasping elements for anchoring the prosthetic valve, mutatis mutandis.

Reference is now made to <figref idref="DRAWINGS">FIGS. 6A-B</figref>, which are schematic illustrations of prosthetic valve <b>80</b>, the prosthetic valve comprising a sealing material <b>110</b> on an outer surface of the valve, in accordance with some applications of the present invention. For some applications, prosthetic valve <b>80</b> is used in conjunction with prosthetic valve support <b>40</b>, as described hereinabove. The techniques for implanting prosthetic valve <b>80</b> as shown in <figref idref="DRAWINGS">FIGS. 6A-B</figref> are generally similar to those described hereinabove. Typically, sealing material <b>110</b> seals the interface between the prosthetic valve and native valve <b>5</b>. The sealing material reduces retrograde blood flow from ventricle <b>6</b> into atrium <b>4</b>, relative to retrograde blood flow in the absence of the sealing material. Typically, the sealing material is composed of latex, dacron, and/or any other suitable biocompatible material. The sealing material is typically placed around at least a portion of expandable frame <b>79</b> of the prosthetic valve so as to form a webbing between struts of the expandable frame.

Reference is now made to <figref idref="DRAWINGS">FIGS. 7A-F</figref>, which are schematic illustrations of a guide wire delivery system, in accordance with some applications of the present invention. As described hereinabove (e.g., with reference to <figref idref="DRAWINGS">FIGS. 2C-F</figref>), for some applications, guide members <b>21</b><i>a </i>and <b>21</b><i>b</i>, function as valve support guide members, by support <b>40</b> being slid along guide members <b>21</b><i>a </i>and <b>21</b><i>b</i>. For some applications, only one guide member <b>21</b> is looped through commissures <b>8</b> and <b>10</b> in a manner in which the guide member defines a looped portion between commissures <b>8</b> and <b>10</b> (i.e., a portion of the guide member that is disposed in a ventricle <b>6</b> of heart <b>2</b>), and first and second free ends, which are disposed and accessible at a site outside the body of the patient. For such applications, the guide member defines portions <b>21</b><i>a </i>and <b>21</b><i>b. </i>

For some applications, an anchor <b>302</b> is advanced toward the vicinity of apex <b>304</b> of heart <b>2</b>, via sheath <b>25</b>, and is anchored to the vicinity of the apex, as shown in <figref idref="DRAWINGS">FIG. 7A</figref>. A guidewire <b>306</b> extends proximally from anchor. Guide member <b>21</b> passes through a guide member tube <b>320</b>, the guide member tube being coupled to guidewire <b>306</b>. Guide member <b>21</b> is pushed distally. Guide member tube <b>320</b> is unable to advance distally over guidewire <b>306</b>, due to the coupling of the guide member tube to the guidewire. Therefore, the pushing of guide member <b>21</b> distally, causes portions <b>21</b><i>a </i>and <b>21</b><i>b </i>to spread apart from one another and to be pushed against commissures <b>8</b> and <b>10</b> of native valve <b>5</b>. Portions <b>21</b><i>a </i>and <b>21</b><i>b </i>are then used to guide valve support <b>40</b> to the commissures, as shown in <figref idref="DRAWINGS">FIGS. 7B-C</figref>, using generally similar techniques to those described hereinabove, except for the differences described hereinbelow.

As shown in <figref idref="DRAWINGS">FIG. 7B</figref>, valve support <b>40</b> is slid over guide member portions <b>21</b><i>a </i>and <b>21</b><i>b</i>, by pushing elements <b>52</b><i>a </i>and <b>52</b><i>b</i>. Since the guide member portions are positioned at commissures <b>8</b> and <b>10</b>, the guide member portions guide the distal ends of pushing elements <b>52</b><i>a </i>and <b>52</b><i>b</i>, such that the pushing elements push the valve support against the commissures, as shown in <figref idref="DRAWINGS">FIG. 7C</figref>.

Subsequent to the placement of valve support <b>40</b> at the native valve, prosthetic atrioventricular valve <b>80</b> is coupled to valve support <b>40</b>. For some applications, pushing elements <b>52</b><i>a </i>and <b>52</b><i>b </i>continue to push the valve support against the native valve, during the coupling of the prosthetic valve to the valve support. As described hereinabove, overtube <b>70</b> is advanced into ventricle <b>6</b>, as shown in <figref idref="DRAWINGS">FIG. 7D</figref>. <figref idref="DRAWINGS">FIG. 7E</figref> shows prosthetic valve having been partially deployed in the ventricle. Following the partial deployment of valve <b>80</b> in ventricle <b>6</b>, overtube <b>70</b> is pulled proximally to pull valve <b>80</b> proximally such that cylindrical element <b>42</b> and/or annular element <b>44</b> of valve support <b>40</b> surrounds a proximal portion of prosthetic valve <b>80</b>. Valve <b>80</b> has a tendency to expand such that valve <b>80</b> is held in place with respect to valve support <b>40</b> responsively to radial forces acted upon valve support <b>40</b> by prosthetic valve <b>80</b>. During the pulling back of overtube <b>70</b>, pushing elements <b>52</b><i>a </i>and <b>52</b><i>b </i>push valve support <b>40</b> against the valve, thereby providing a counter force against which overtube <b>70</b> is pulled back. For some applications, the pushing of the valve support against the commissures is such that it is not necessary to use anchors for anchoring the valve support to the native valve during the coupling of the prosthetic valve to the valve support. Alternatively, in addition to the pushing elements providing a counter force against which the prosthetic valve is pulled, anchors are used to anchor the valve support to the native valve during the coupling of the prosthetic valve to the valve support.

As described hereinabove, valve <b>80</b> comprises a plurality of distal protrusions <b>84</b>. When valve <b>80</b> is pulled proximally, as described hereinabove, protrusions <b>84</b> ensnare and engage the native leaflets of the atrioventricular valve. By the ensnaring of the native leaflets, protrusions <b>84</b> sandwich the native valve between protrusions <b>84</b> and prosthetic valve support <b>40</b>. Such ensnaring helps further anchor prosthetic valve <b>80</b> to the native atrioventricular valve.

For some applications, as described hereinabove, protrusions <b>84</b> are such as to (a) prevent proximal migration of the valve into the patient's atrium, while (b) allowing movement of the native leaflets with respect to the frame of the prosthetic valve. For example, the protrusions may have the aforementioned functionalities by having lengths of less than 5 mm and/or by a total width of each set of protrusions corresponding to respective leaflets of the native valve being less than 5 mm. For example, the valve may include a single protrusion corresponding to each leaflet of the native valve, the width of each of the single protrusions being less than 1 mm. Thus, the valve may be stopped from proximally migrating into the atrium, by the protrusions preventing the distal end of the valve from migrating further proximally than edges of native leaflets of the valve. Furthermore, the protrusions may allow movement of the native leaflets with respect to the frame of the prosthetic valve by not generally squeezing the native leaflets between the protrusions and the frame of the valve. For some applications, by allowing movement of the native leaflets with respect to the frame of the prosthetic valve, sealing of the native leaflets against the outer surface of the frame of the prosthetic valve is facilitated, in accordance with the techniques described hereinbelow with reference to <figref idref="DRAWINGS">FIG. 10</figref>.

Subsequent to the placement of the prosthetic valve at the native valve, sheath <b>25</b>, overtube <b>70</b>, pushing elements <b>52</b><i>a </i>and <b>52</b><i>b</i>, guide member <b>21</b>, anchor <b>302</b>, and guidewire <b>306</b> are removed from the patient's body, as shown in <figref idref="DRAWINGS">FIG. 7F</figref>, which shows the prosthetic valve in its deployed state. For some applications, in order to remove guide member <b>21</b> from the patient's body, guide member portions <b>21</b><i>a </i>and <b>21</b><i>b </i>are decoupled from guide member tube <b>320</b>. For example, the guide member portions may be coupled to the guide member tube via threading, the guide member portions being decoupled from the guide member tube by unscrewing the guide member portions from the guide member tube.

Reference is now made to <figref idref="DRAWINGS">FIGS. 8A-C</figref> which are schematic illustrations of a system <b>120</b> comprising an invertible valve support <b>140</b>, in accordance with some applications of the present invention. Invertible valve support <b>140</b> is identical to valve support <b>40</b> described herein, with the exception that the cylindrical element of valve support <b>140</b> is invertible, as is described hereinbelow. Additionally, the method of advancing toward and implanting valve support <b>140</b> at annulus <b>11</b> is identical to the methods of advancing toward and implanting valve support <b>40</b> at annulus <b>11</b>, as described hereinabove.

Valve support <b>140</b> comprises an annular element <b>144</b> (that is identical to annular element <b>44</b> described hereinabove) and a cylindrical element <b>142</b>. Cylindrical element <b>142</b> has a first end <b>150</b>, a second end <b>152</b>, and a cylindrical body <b>153</b> disposed between first and second ends <b>150</b> and <b>152</b>. Cylindrical element <b>142</b> is attached to annular element <b>144</b> at first end <b>150</b> of cylindrical element <b>142</b>.

During and following implantation of support <b>140</b> at annulus <b>11</b>, as shown in <figref idref="DRAWINGS">FIG. 8A</figref>, cylindrical element <b>142</b> is disposed above annular element <b>144</b> in a manner in which second end <b>152</b> and cylindrical body <b>153</b> are disposed above annular element <b>144</b> and within atrium <b>4</b>. One or more elongate guide members <b>146</b><i>a </i>and <b>146</b><i>b </i>are reversibly coupled to cylindrical element <b>142</b> in a vicinity of second end <b>152</b>. Elongate guide members <b>146</b><i>a </i>and <b>146</b><i>b </i>facilitate (a) advancement of prosthetic valve <b>80</b> therealong and toward valve support <b>140</b>, and (b) inversion of cylindrical element <b>142</b> toward ventricle <b>6</b> when at least a portion of valve <b>80</b> is deployed within ventricle <b>6</b> (as shown in <figref idref="DRAWINGS">FIG. 8B</figref>).

The configuration of valve support <b>140</b> as shown in <figref idref="DRAWINGS">FIG. 8A</figref> (i.e., the configuration in which cylindrical element <b>142</b> is disposed within atrium <b>4</b>) eliminates the obstruction of native valve <b>5</b> and of leaflets <b>12</b> and <b>14</b> by any portion of valve support <b>140</b>. In this manner, valve support <b>140</b> may be implanted at valve <b>5</b> while valve <b>5</b> resumes its native function and leaflets <b>12</b> and <b>14</b> resume their natural function (as shown by the phantom drawing of leaflets <b>12</b> and <b>14</b> in <figref idref="DRAWINGS">FIG. 8A</figref> which indicates their movement). This atrially-inverted configuration of valve support <b>140</b> reduces and even eliminates the amount of time the patient is under cardiopulmonary bypass. Only once prosthetic valve <b>80</b> is delivered and coupled to valve support <b>140</b> and cylindrical element <b>142</b> is thereby ventricularly-inverted, native leaflets <b>12</b> and <b>14</b> are pushed aside (<figref idref="DRAWINGS">FIG. 8B</figref>).

<figref idref="DRAWINGS">FIG. 8B</figref> shows the inversion of cylindrical element <b>142</b> by the partial positioning and deployment of prosthetic valve <b>80</b> within ventricle <b>6</b>. Elongate guide members <b>146</b><i>a </i>and <b>146</b><i>b </i>are reversibly coupled to prosthetic valve <b>80</b> and extend within overtube <b>70</b>. Following the full deployment of valve <b>80</b> and the coupling of valve <b>80</b> to valve support <b>140</b>, elongate guide members <b>146</b><i>a </i>and <b>146</b><i>b </i>are decoupled from prosthetic valve <b>80</b> and from cylindrical element <b>142</b>. For example, a cutting tool may be used to decouple elongate members <b>146</b><i>a </i>and <b>146</b><i>b </i>from the valve support <b>140</b>. Alternatively, elongate members <b>146</b><i>a </i>and <b>146</b><i>b </i>may be looped through the cylindrical element <b>142</b>, such that both ends of each elongate member <b>146</b><i>a </i>and <b>146</b><i>b </i>remain outside of the patient's body. The operating physician decouples elongate members <b>146</b><i>a </i>and <b>146</b><i>b </i>from valve support <b>140</b> by releasing one end of each of elongate members <b>146</b><i>a </i>and <b>146</b><i>b </i>and pulling on the other end, until elongate members <b>146</b><i>a </i>and <b>146</b><i>b </i>are drawn from valve support <b>140</b> and removed from within the body of the patient.

<figref idref="DRAWINGS">FIG. 8C</figref> shows prosthetic valve <b>80</b> coupled to valve support <b>140</b>. Valve <b>80</b> is identical to the valve described hereinabove.

Reference is now made to <figref idref="DRAWINGS">FIGS. 9A-E</figref>, which are schematic illustrations of the advancement of an invertible prosthetic valve support <b>300</b> toward a native atrioventricular valve of a patient, and inversion of the valve support, in accordance with some applications of the present invention. Prosthetic valve support <b>300</b> is used to anchor prosthetic valve <b>80</b> to native valve <b>5</b> in a generally similar manner to that described with reference to prosthetic valve support <b>40</b>.

During a typical procedure, anchor <b>302</b> is advanced toward the vicinity of apex <b>304</b> of heart <b>2</b>, via sheath <b>25</b>, and is anchored to the vicinity of the apex, as shown in <figref idref="DRAWINGS">FIG. 8A</figref>. A guidewire <b>306</b> extends proximally from anchor. A distal tensioning element <b>308</b> (e.g., a plunger) is advanced over guidewire <b>306</b> into ventricle <b>6</b>, and prosthetic valve support <b>300</b> is advanced out of the distal end of sheath <b>25</b>, as shown in <figref idref="DRAWINGS">FIG. 9B</figref>. A first end <b>310</b> of prosthetic valve support <b>300</b> (which at this stage is the distal end of the prosthetic valve support), comprises barbs <b>314</b> (shown in <figref idref="DRAWINGS">FIG. 9B</figref>), or other anchoring elements for anchoring the first end of the prosthetic valve support to tissue of native valve <b>5</b>. Prosthetic valve support <b>300</b> is pushed distally such that the barbs are pushed into the native valve tissue, thereby anchoring the first end of the prosthetic valve support to the native valve, as shown in <figref idref="DRAWINGS">FIG. 9C</figref>. A plurality of wires <b>309</b> pass from distal tensioning element <b>308</b> to a proximal tensioning element <b>311</b> (shown in <figref idref="DRAWINGS">FIG. 9D</figref>), via a second end <b>312</b> of valve support <b>300</b> (which at this stage is the proximal end of the prosthetic valve support). For some applications, a sealing element <b>316</b> is disposed circumferentially around a surface of the invertible prosthetic valve support that is initially an inner surface of the invertible prosthetic valve support (a shown in <figref idref="DRAWINGS">FIGS. 8A-D</figref>). For example, the sealing material may be latex, dacron, or another suitable biocompatible sealing material.

Subsequent to the anchoring of first end <b>310</b> of prosthetic valve support <b>300</b> to native valve tissue (as shown in <figref idref="DRAWINGS">FIG. 9C</figref>), distal tensioning element <b>308</b> is further advanced distally into ventricle <b>6</b>, and proximal tensioning element <b>311</b> is advanced toward the ventricle. As shown in the transition from <figref idref="DRAWINGS">FIG. 9D-F</figref>, as the proximal tensioning element passes through the valve support, wires <b>309</b> cause valve support <b>300</b> to invert, by pulling second end <b>312</b> of the valve support through first end <b>310</b> of the valve support. Subsequent to the inversion of the valve support, sealing material <b>316</b> is disposed circumferentially around the outside of the valve support, thereby providing a seal at the interface between valve support <b>300</b> and native valve <b>5</b>.

Reference is now made to <figref idref="DRAWINGS">FIGS. 9G-H</figref>, which are schematic illustrations of the deployment of prosthetic valve <b>80</b> and the coupling of the prosthetic valve to invertible valve support <b>300</b>, in accordance with some applications of the present invention.

The deployment of prosthetic valve <b>80</b> is generally similar to the techniques described hereinabove with reference to <figref idref="DRAWINGS">FIGS. 2H-J</figref>. The valve is partially deployed in ventricle <b>6</b>, via overtube <b>70</b>. Following the partial deployment of valve <b>80</b> in ventricle <b>6</b>, overtube <b>70</b> is pulled proximally (as shown in <figref idref="DRAWINGS">FIG. 8G</figref>) to pull valve <b>80</b> proximally such that valve support <b>300</b> surrounds a proximal portion of prosthetic valve <b>80</b>, as shown in <figref idref="DRAWINGS">FIG. 8H</figref>. Valve <b>80</b> has a tendency to expand such that valve <b>80</b> is held in place with respect to valve support <b>300</b> responsively to radial forces acted upon valve support <b>300</b> by prosthetic valve <b>80</b>.

As described hereinabove, for some applications, valve <b>80</b> comprises a plurality of distal protrusions <b>84</b>. When valve <b>80</b> is pulled proximally, protrusions <b>84</b> ensnare and engage the native leaflets of the atrioventricular valve. By the ensnaring of the native leaflets, protrusions <b>84</b> sandwich the native valve between protrusions <b>84</b> and prosthetic valve support <b>300</b>. Such ensnaring helps further anchor prosthetic valve <b>80</b> to the native atrioventricular valve.

For some applications, as described hereinabove, protrusions <b>84</b> are such as to (a) prevent proximal migration of the valve into the patient's atrium, while (b) allowing movement of the native leaflets with respect to the frame of the prosthetic valve. For example, the protrusions may have the aforementioned functionalities by having lengths of less than 5 mm, and/or by a total width of each set of protrusions corresponding to respective leaflets of the native valve being less than 5 mm. For example, the valve may include a single protrusion corresponding to each leaflet of the native valve, the width of each of the single protrusions being less than 1 mm. Thus, the valve may be stopped from proximally migrating into the atrium, by the protrusions preventing the distal end of the valve from migrating further proximally than edges of native leaflets of the valve. Furthermore, the protrusions may allow movement of the native leaflets with respect to the frame of the prosthetic valve by not generally squeezing the native leaflets between the protrusions and the frame of the valve. For some applications, by allowing movement of the native leaflets with respect to the frame of the prosthetic valve, sealing of the native leaflets against the outer surface of the frame of the prosthetic valve is facilitated, in accordance with the techniques described hereinbelow with reference to <figref idref="DRAWINGS">FIG. 10</figref>.

Additionally, as shown in <figref idref="DRAWINGS">FIG. 9H</figref>, and as described hereinabove, valve <b>80</b> comprises one or more coupling elements <b>81</b> (for example, a plurality of coupling elements, as shown) at the proximal end of valve <b>80</b>. Overtube <b>70</b>, which facilitates the advancement of prosthetic valve <b>80</b>, is reversibly coupled to valve <b>80</b>, via coupling elements <b>81</b>.

Subsequent to the coupling of valve <b>80</b> to valve support <b>300</b>, overtube <b>70</b>, distal and proximal tensioning elements <b>308</b> and <b>311</b>, and wires <b>309</b> are removed from the patient's body, via sheath <b>25</b>. Typically, wires <b>309</b> are cut, in order to facilitate the removal of the wires from the patient's body. Guidewire <b>306</b> and anchor <b>302</b> are removed from the patient's body by detaching the anchor from apex <b>304</b>, and withdrawing the anchor and the guidewire, via sheath <b>25</b>.

Reference is now made to <figref idref="DRAWINGS">FIG. 10</figref>, which is a schematic illustration of prosthetic valve <b>80</b>, for placing inside atrioventricular valve <b>5</b> of the patient, in accordance with some applications of the present invention. The expandable frame <b>79</b> of the prosthetic valve has a diameter d, and a corresponding cross-sectional area. Native annulus <b>11</b>, which is typically saddle-shaped, defines an area A, as shown. For some applications, area A, which is defined by the native annulus is measured, e.g., using a measuring ring. A prosthetic valve is chosen to be placed in the annulus, the cross-sectional area of the prosthetic valve being less than 90% (e.g., less than 80%, or less than 60%) of area A. For some applications, diameter d of the prosthetic valve is less than 25 mm, e.g., less than 20 mm, and/or more than 15 mm, e.g., 15-25 mm. For some applications, placing a prosthetic valve inside the native valve with the dimensions of the native valve annulus and the prosthetic valve as described, facilitates sealing of the prosthetic valve with respect to the native valve, by the native valve leaflets closing around the outer surface of the prosthetic valve.

For some applications, a prosthetic valve support <b>40</b> that includes annular element <b>44</b> (e.g., as shown in <figref idref="DRAWINGS">FIGS. 14A-C</figref>) is chosen to be placed at the annulus, the annular element defining an inner cross-sectional area that is less than 90% (e.g., less than 80%, or less than 60%) of area A. Prosthetic valve <b>80</b> is deployed at the native valve by coupling the prosthetic valve to the prosthetic valve support at the location, responsively to radial forces acted upon the valve support by the expandable frame, by facilitating expansion of the expandable frame, as described herein. The cross-sectional area defined by the expandable frame of the prosthetic valve, upon expansion of the expandable frame, is limited by the cross-sectional area defined by the annular element of the prosthetic valve support to less than 90% (e.g., less than 80%, or less than 60%) of area A. For some applications, placing a prosthetic valve support at the annulus with the dimensions of the native valve annulus and valve support <b>40</b>, as described, facilitates sealing of the prosthetic valve with respect to the native valve, by the native valve leaflets closing around the outer surface of the prosthetic valve.

Typically, placing a prosthetic valve inside the native valve with the dimensions of the native valve annulus, the prosthetic valve <b>80</b>, and/or valve support <b>40</b> as described in the above paragraphs, facilitates sealing of the prosthetic valve with respect to the native valve. For some applications, the sealing is facilitated by the native leaflets being pushed against, and closing against, the outer surface of the frame of the valve during systole, in a similar manner to the manner in which native valve leaflets coapt during systole, in a healthy mitral valve. Typically, as the diameter of the prosthetic valve is increased, the length of the native leaflets that is pushed against the outer surface of the valve during systole is increased, thereby enhancing the sealing of the native leaflets with respect to the frame of the prosthetic valve. However, beyond a given diameter, as the diameter of the prosthetic valve is increased, the native valve leaflets are pushed apart at the commissures, thereby causing retrograde leakage of blood through the commissures. Therefore, in accordance with some applications of the present invention, prosthetic valve <b>80</b>, and/or valve support <b>40</b> are chosen such that the cross-sectional area of the prosthetic valve when expanded inside the valve support is less than 90% (e.g., less than 80%, or less than 60%) of area A. Thus the valve support facilitates sealing of the prosthetic valve with respect to the native valve, by the native valve leaflets closing around the outer surface of the prosthetic valve, while not causing retrograde leakage of blood through the commissures.

For some applications, in order to facilitate the sealing of the native valve around the outer surface of the prosthetic valve, a material is placed on the outer surface of the prosthetic valve in order to provide a sealing interface between the prosthetic valve and the native valve. For example, a smooth material that prevents tissue growth (e.g., polytetrafluoroethylene (PTFE), and/or pericardium) may be placed on the outer surface of the prosthetic valve. Alternatively or additionally, a material that facilitates tissue growth (such as dacron) may be placed on the outer surface of the prosthetic valve, in order to (a) act as a sealing interface between the native valve and the prosthetic valve, and (b) facilitate tissue growth around the prosthetic valve to facilitate anchoring and/or sealing of the prosthetic valve.

Reference is now made to <figref idref="DRAWINGS">FIGS. 11A-D</figref>, which are schematic illustrations of prosthetic valve <b>80</b>, in accordance with some applications of the present invention. For some applications, protrusions <b>84</b> are disposed on the valve on portions <b>400</b> of the valve that are placed adjacent to the anterior and posterior leaflets of the native valve, and the valve does not includes protrusions on portions <b>402</b> of the valve that are placed adjacent to the commissures of the native valve.

<figref idref="DRAWINGS">FIGS. 11B-D</figref> show bottom views (i.e., views of the distal ends) of respective configurations of prosthetic valve <b>80</b> and protrusions <b>84</b>. The protrusions converge from the proximal ends <b>404</b> of the protrusion to the distal ends <b>406</b> of the protrusions. The protrusions are configured such as to ensnare chordae tendineae, and to pull the chordae tendineae toward each other when the prosthetic valve is pulled proximally, due to the convergence of the snares with respect to each other. <figref idref="DRAWINGS">FIG. 11D</figref> shows the prosthetic valve deployed at native valve <b>5</b>. As shown, the protrusions ensnare chordae tendineae <b>102</b> of the patient. The protrusions facilitate sealing and anchoring of the prosthetic valve with respect to the native valve by pulling the chordae tendinae toward each other, as described. As described hereinabove, for some applications the prosthetic valve does not define protrusions <b>84</b> on portions <b>402</b> that are placed next to the native commissures, e.g., commissure <b>8</b>, shown in <figref idref="DRAWINGS">FIG. 11D</figref>.

For some applications, as described hereinabove, protrusions <b>84</b> are such as to (a) prevent proximal migration of the valve into the patient's atrium, while (b) allowing movement of the native leaflets with respect to the frame of the prosthetic valve. For example, the protrusions may have the aforementioned functionalities by having lengths of less than 5 mm, and/or by a total width of each set of protrusions corresponding to respective leaflets of the native valve being less than 5 mm. For example, the valve may include a single protrusion corresponding to each leaflet of the native valve, the width of each of the single protrusions being less than 1 mm. Thus, the valve may be stopped from proximally migrating into the atrium, by the protrusions preventing the distal end of the valve from migrating further proximally than edges of native leaflets of the valve. Furthermore, the protrusions may allow movement of the native leaflets with respect to the frame of the prosthetic valve by not generally squeezing the native leaflets between the protrusions and the frame of the valve. For some applications, by allowing movement of the native leaflets with respect to the frame of the prosthetic valve, sealing of the native leaflets against the outer surface of the frame of the prosthetic valve is facilitated, in accordance with the techniques described hereinabove with reference to <figref idref="DRAWINGS">FIG. 10</figref>.

For some applications, a first set of protrusions <b>84</b> from the distal end of prosthetic valve <b>80</b> are disposed within a first circumferential arc with respect to a longitudinal axis of the prosthetic valve, on a first side of the distal end of the prosthetic valve, the first side of the distal end being configured to be placed adjacent to the anterior leaflet of the native valve. A second set of protrusions are disposed within a second circumferential arc with respect to a longitudinal axis of the prosthetic valve, on a second side of the distal end of the prosthetic valve, the second side of the distal end being configured to be placed adjacent to the posterior leaflet of the native valve.

The first and second sets of protrusions are disposed so as to provide first and second gaps therebetween at the distal end of the prosthetic valve. Typically, at least one of the gaps between the two sets of protrusions has a circumferential arc of at least 20 degrees (e.g., at least 60 degrees, or at least 100 degrees), and/or less than 180 degrees (e.g., less than 140 degrees), e.g., 60-180 degrees, or 100-140 degrees. Further typically, one or both of the first and second circumferential arcs defines an angle of at least 25 degrees (e.g., at least 45 degrees), and/or less than 90 degrees (e.g., less than 75 degrees), e.g., 25-90 degrees, or 45-75 degrees.

Valve guide members (e.g., guide members <b>21</b><i>a </i>and <b>21</b><i>b</i>, and/or delivery lumen <b>27</b><i>a </i>and <b>27</b><i>b</i>, as described hereinabove) are delivered to commissures of the native valve, and guide the valve such that the first and second circumferential arc are aligned with respective leaflets of the native valve and such that the first and second gaps are aligned with respective commissures of the native valve.

Reference is now made to <figref idref="DRAWINGS">FIGS. 12A-C</figref>, which are schematic illustrations of prosthetic valve <b>80</b>, the valve defining distal protrusions <b>84</b> that are disposed sinusoidally around the circumference of the valve, in accordance with some applications of the present invention. For some applications the protrusions are shaped sinusoidally, in order to conform with the saddle-shape of native valve annulus <b>11</b>, thereby facilitating the sandwiching of the native valve leaflets between the protrusions and valve support <b>40</b>. As shown, the peaks of the sinusoid that is defined by the protrusions is disposed on portions <b>402</b> that are placed next to the native commissures and the troughs of the sinusoid is placed on portions of the valve that are placed in the vicinity of the centers of the anterior and posterior leaflets of the native valve. As shown in <figref idref="DRAWINGS">FIG. 12C</figref>, for some applications the distal end of the prosthetic valve defines a sinusoidal shape.

Reference is now made to <figref idref="DRAWINGS">FIGS. 13A-E</figref>, which are schematic illustrations of respective configurations of expandable frame <b>79</b> of prosthetic valve <b>80</b>, in accordance with some applications of the present invention. As described hereinabove, for some applications, valve <b>80</b> defines distal protrusions <b>84</b> that are configured to facilitate sandwiching of the native valve leaflets between the protrusions and valve support <b>40</b>. For some applications, tips of the distal protrusions are shaped so as to prevent the tips from piercing, and/or otherwise damaging, tissue of the native leaflets. For example, the tips of the protrusions may be curved, as shown in <figref idref="DRAWINGS">FIG. 13A</figref>. Or, the distal tips of the protrusions may be shaped as balls, as shown in <figref idref="DRAWINGS">FIG. 13</figref>, and/or a different rounded shape. For some applications, the distal tip of each of the protrusions is joined to the distal tip of an adjacent protrusion by an arch <b>410</b>, as shown in <figref idref="DRAWINGS">FIGS. 13C and 13D</figref>.

For some applications, the protrusions are configured to be distally-facing during the insertion of prosthetic valve <b>80</b> into the subject's left ventricle. For example, the valve may be inserted through overtube <b>70</b> (shown in <figref idref="DRAWINGS">FIG. 7E</figref>, for example). The valve is crimped during the insertion of the valve through the overtube, and the protrusions are constrained in their distally-facing configurations by the overtube. The protrusions are pre-shaped such that in the resting state of the protrusions, the protrusions assume proximally-facing configurations, as shown in <figref idref="DRAWINGS">FIG. 13D</figref>, for example. Thus, upon emerging from overtube <b>70</b>, the protrusions assume proximally-facing configurations. For some applications, when the protrusions assume the proximally-facing configurations, the protrusions are disposed at an angle theta (<figref idref="DRAWINGS">FIG. 13D</figref>) from expandable frame <b>79</b> of more than 40 degrees (e.g., more than 50 degrees), and/or less than 80 degrees (e.g., less than 70 degrees).

Typically, protrusions <b>84</b> are coupled to frame <b>79</b> of valve <b>80</b> at joints <b>412</b>. For some applications, joints <b>412</b> are thinner than portions of the protrusions and of the frame surrounding the joints, as shown in <figref idref="DRAWINGS">FIG. 13D</figref>. For some applications, the thinness of the joints with respect to the surrounding portions facilitates the crimping of the protrusions into distally-facing configuration during the insertion of the valve into the heart.

For some applications, barbs <b>416</b> extend from a proximal portion of expandable frame <b>79</b> of valve <b>80</b>, as shown in <figref idref="DRAWINGS">FIG. 13E</figref>. For example, the barbs may be configured to anchor the prosthetic valve to the native valve by piercing tissue of the native valve. Alternatively or additionally, the barbs may be configured to anchor the prosthetic valve to the valve support <b>40</b>, by becoming coupled to portions of the valve support. For some applications the barbs protrude from the top-central corner of respective cells of expandable frame <b>79</b>. Typically, when the prosthetic valve is crimped, the barbs fit within gaps of respective cells of the expandable frame, and do not substantially increase the crimping profile of the prosthetic valve, relative to a generally similar prosthetic valve that does not include barbs.

For some applications, the barbs are not generally used for coupling prosthetic valve support <b>80</b> to valve support <b>40</b>. Rather, the prosthetic valve is coupled to the valve support by virtue of radial expansion of the prosthetic valve against annular element <b>44</b> of the valve support. Barbs <b>416</b> are used to prevent prosthetic valve from migrating distally into the patient's left ventricle, and/or to prevent valve support <b>40</b> from migrating proximally into the subject's left atrium.

For some applications (not shown), barbs protrude from coupling elements <b>81</b> of prosthetic valve <b>80</b>, the barbs being generally similar in shape and function to that described with reference to barbs <b>416</b>. For some applications (not shown), radially-inwardly facing barbs <b>45</b> protrude from annular element <b>44</b> of valve support <b>40</b>, as shown in <figref idref="DRAWINGS">FIG. 14D</figref>. As described with reference to barbs <b>416</b>, the barbs that protrude from annular element <b>44</b> may facilitate coupling of the prosthetic valve to the valve support. Alternatively or additionally, the barbs that protrude from annular element <b>44</b> are used to prevent prosthetic valve from migrating distally into the patient's left ventricle, and/or to prevent valve support <b>40</b> from migrating proximally into the subject's left atrium.

For some applications, a proximal end of expandable frame <b>79</b> of prosthetic valve <b>80</b> defines a larger cross-section area than more distal portions of the expandable frame. For example, the expandable frame may have a frustoconical shape, the walls of the expandable frame diverging from a distal end of the frame to a proximal end of the frame. Alternatively, the expandable frame may have a trumpet shape (i.e., the frame may be generally tubular, with a dilated proximal end). For some applications, the larger cross-sectional area of the proximal end of the frame prevents the prosthetic valve from migrating distally into the patient's left ventricle, and/or prevents valve support <b>40</b> from migrating proximally into the subject's left atrium.

Reference is now made to <figref idref="DRAWINGS">FIGS. 14A-D</figref>, which are schematic illustrations of respective configurations of prosthetic valve support <b>40</b>, in accordance with some applications of the present invention. As described hereinabove, for some applications, the valve support comprises a collapsible skirt having a proximal annular element <b>44</b> and a distal cylindrical element <b>42</b> (e.g., as shown in <figref idref="DRAWINGS">FIG. 2D</figref>). Alternatively, the valve support does not include a distal cylindrical element. For example, the valve support may only include annular element <b>44</b>. As described hereinabove, annular element <b>44</b> is configured to be placed around native annulus <b>11</b> of the native valve, and to extend at least partially into atrium <b>4</b> such that annular element <b>44</b> rests against the native annulus. Annular element <b>44</b> is typically too large to pass through the annulus, and may, for example, have an outer diameter of between 30 and 60 mm.

<figref idref="DRAWINGS">FIGS. 14A-D</figref> show annular element <b>44</b> of valve support <b>40</b> in respective configurations, in accordance with some applications of the present invention. For some applications, the annular element is D-shaped, as shown in <figref idref="DRAWINGS">FIG. 14A</figref>. Alternatively or additionally, the annular element has a generally round shape, as shown in <figref idref="DRAWINGS">FIGS. 14B-C</figref>. For some applications the annular element is asymmetrical. For example, <figref idref="DRAWINGS">FIG. 14B</figref> shows a generally rounded annular element that is wider on a first side <b>420</b> of the element than on a second side <b>422</b> of the element. Typically, the wider side of the annular element is placed on the anterior side of the native annulus. In accordance with some applications, the annular element is symmetrical, asymmetrical, oval, round, defines a hole that is centered with respect to the annular element, and/or defines a hole that is off-center with respect to the annular element. For some applications, the stiffness of the annular element varies around the circumference of the annular element.

For some applications, annular element <b>44</b> is asymmetrical, as shown in <figref idref="DRAWINGS">FIG. 14B</figref>. Typically, the asymmetry of the annular element is such that the center of the hole defined by the annular element is disposed asymmetrically (i.e., off-center) with respect to the center of the annular element, as defined by the outer perimeter of the annular element. For some applications, the asymmetric disposition of the center of the hole defined by the annular element is such that when the prosthetic valve is placed inside the annular element, the longitudinal axis of the prosthetic valve is disposed asymmetrically (i.e., off-center) with respect to the center of the annular element, as defined by the outer perimeter of the annular element. Typically, the annular element is shaped such that, when the annular element is placed on the patient's mitral annulus, and the prosthetic valve is expanded inside the annular element, the longitudinal axis of the prosthetic valve is disposed in the vicinity of the location at which the patient's native leaflets coapt (this location being off-center with respect to the patient's native mitral annulus).

For some applications (not shown), radially-inwardly facing barbs <b>45</b> protrude from annular element <b>44</b> of valve support <b>40</b>, as shown in <figref idref="DRAWINGS">FIG. 14D</figref>. As described with reference to barbs <b>416</b> shown protruding from prosthetic valve <b>80</b> in <figref idref="DRAWINGS">FIG. 13E</figref>, the barbs that protrude from annular element <b>44</b> may facilitate coupling of the prosthetic valve to the valve support. Alternatively or additionally, the barbs that protrude from annular element <b>44</b> are used to prevent prosthetic valve from migrating distally into the patient's left ventricle, and/or to prevent valve support <b>40</b> from migrating proximally into the subject's left atrium. For some applications, some or all of barbs <b>102</b> are curved. Typically, the curved barbs curve away from the plane of annular element <b>40</b>, such that, when implanted, barbs <b>102</b> point into the patient's atrium.

Typically, the annular element includes frame <b>48</b>, the frame being covered at least in part with covering <b>49</b>, e.g., fabric. Typically, the upper surface of annular element <b>44</b> is covered with fabric, for example, in order to provide a generally smooth surface for coming into contact with the patient's blood flow. Further typically, the lower surface of the annular element (i.e., the side of the annular element that is placed in contact with the native annulus) is not covered with fabric, for example, in order to reduce a crimped volume (or cross-sectional area) of the annular element, relative to the volume of the annular element if the lower surface of the annular element were covered in fabric. Typically, a thickness of the fabric layer is less than 0.2 mm, e.g., less than 0.1 mm, or less than 0.05 mm.

For some applications, the side of the annular element that is placed in contact with the native annulus is covered with the fabric, the fabric being configured to facilitate coupling of the annular element to the native annulus, by facilitating fibrosis at the interface between the annular element and the native annulus. For some applications, the upper surface of the annular element is not covered with fabric. For example, the upper surface may not be covered in fabric in order to reduce a crimped volume (or cross-sectional area) of the annular element, relative to the volume of the annular element if the upper surface of the annular element were covered in fabric.

For some applications, annular element <b>44</b> is not covered with fabric, and/or is not configured to form a seal against frame <b>79</b> of prosthetic valve <b>80</b>. For some applications, the annular element is configured to allow leakage of blood between the annular element and frame <b>79</b> of prosthetic valve <b>80</b>. For example, the annular element may be configured to allow leakage of blood through the interface between the annular element and the frame of the prosthetic valve, in order to accommodate a flow of blood between the patient's atrium and the patient's ventricle that is greater than can be accommodated by blood flowing through the leaflets of the prosthetic valve.

Reference is now made to <figref idref="DRAWINGS">FIGS. 15A-E</figref>, which are schematic illustrations of respective steps of a procedure for deploying a prosthetic valve, in accordance with some applications of the present invention. As described hereinabove and hereinbelow (for example, with reference to <figref idref="DRAWINGS">FIGS. 2A-K</figref>, <b>7</b>A-F, <b>8</b>A-C, <b>9</b>A-H, and <b>16</b>A-G), for some procedures, valve support <b>40</b> is placed on the valve annulus and, subsequently, prosthetic valve <b>80</b> is inserted into the subject's left ventricle through the valve support. Alternatively, any of the procedures described herein (for example, procedures described with reference to <figref idref="DRAWINGS">FIGS. 2A-K</figref>, <b>7</b>A-F, <b>8</b>A-C, <b>9</b>A-H, and <b>16</b>A-G) may be performed by first placing the prosthetic valve inside the subject's left ventricle, and, subsequently, deploying the valve support at the annulus. For example, <figref idref="DRAWINGS">FIGS. 15A-E</figref> show a procedure in which the prosthetic valve is placed inside the subject's left ventricle, and, subsequently, the valve support is deployed at the annulus.

As shown in <figref idref="DRAWINGS">FIG. 15A</figref>, for some applications, prosthetic valve <b>80</b> is placed in the subject's ventricle, before prosthetic valve support <b>40</b> is placed at the native valve. The prosthetic valve is typically placed in the left ventricle in an undeployed state, via overtube <b>70</b>. Subsequently, the valve support is placed at the native valve using pushing elements, as shown in <figref idref="DRAWINGS">FIG. 15B</figref>. For some applications, three pushing elements <b>52</b><i>a</i>, <b>52</b><i>b</i>, and <b>52</b><i>c </i>are used to push the valve support against the native valve, as shown in <figref idref="DRAWINGS">FIG. 15B</figref>.

Subsequent to the placement of valve support <b>40</b> at the native valve, prosthetic valve <b>80</b> is coupled to valve support <b>40</b>. For some applications, pushing elements <b>52</b><i>a</i>, <b>52</b><i>b</i>, and <b>52</b><i>c </i>continue to push the valve support against the native valve, during the coupling of the prosthetic valve to the valve support. <figref idref="DRAWINGS">FIG. 15C</figref> shows prosthetic valve having been partially deployed in the ventricle.

Following the partial deployment of valve <b>80</b> in ventricle <b>6</b>, overtube <b>70</b> is pulled proximally to pull valve <b>80</b> proximally such that annular element <b>44</b> of valve support <b>40</b> surrounds a proximal portion of prosthetic valve <b>80</b>, as shown in <figref idref="DRAWINGS">FIG. 15D</figref>. Valve <b>80</b> has a tendency to expand such that valve <b>80</b> is held in place with respect to valve support <b>40</b> responsively to radial forces acted upon valve support <b>40</b> by prosthetic valve <b>80</b>. During the pulling back of overtube <b>70</b>, pushing elements <b>52</b><i>a</i>, <b>52</b><i>b</i>, and <b>52</b><i>c </i>push valve support <b>40</b> against the valve, thereby providing a counter force against which overtube <b>70</b> is pulled back. For some applications, the pushing of the valve support against the commissures is such that it is not necessary to use anchors for anchoring the valve support to the native valve during the coupling of the prosthetic valve to the valve support. Alternatively, in addition to the pushing elements providing a counter force against which the prosthetic valve is pulled, anchors are used to anchor the valve support to the native valve during the coupling of the prosthetic valve to the valve support.

As described hereinabove, valve <b>80</b> comprises a plurality of distal protrusions <b>84</b>. When valve <b>80</b> is pulled proximally, as described hereinabove, protrusions <b>84</b> ensnare and engage the native leaflets of the atrioventricular valve. By the ensnaring of the native leaflets, protrusions <b>84</b> sandwich the native valve between protrusions <b>84</b> and prosthetic valve support <b>40</b>. Such ensnaring helps further anchor prosthetic valve <b>80</b> to the native atrioventricular valve.

It is noted with reference to <figref idref="DRAWINGS">FIG. 15D</figref> that, typically, annular element <b>44</b> of prosthetic valve support <b>40</b> defines an inner cross-sectional area thereof. As described hereinabove, prosthetic valve <b>80</b> includes expandable frame <b>79</b>, and prosthetic leaflets <b>82</b>. The expandable frame of the prosthetic valve is configured such that when the frame is in a non-constrained state thereof, the cross-sectional area of the frame, along at least a given portion L (shown in <figref idref="DRAWINGS">FIG. 15D</figref>) of the length of the frame, is greater than the inner cross-sectional area defined by the annular element of the prosthetic valve support. Typically, during a valve-deployment procedure, a location anywhere along portion L at which to couple the expandable valve to the prosthetic valve support is selected. In response thereto, the location along the portion of the expandable frame is aligned with the annular element of the prosthetic valve support. The expandable valve is then coupled to the prosthetic valve support at the location, responsively to radial forces acted upon the valve support by the expandable frame, by facilitating expansion of the expandable frame, when the location along the portion is aligned with the annular element of the prosthetic valve support.

As described hereinabove, for some applications, expandable frame <b>79</b> of prosthetic valve <b>80</b> has a frustoconical shape. For some applications, the prosthetic valve is coupled to valve support <b>40</b> responsively to radial forces acted upon the valve support by the expandable frame, when a given location along portion L is aligned with annular element <b>44</b> of the prosthetic valve support. For some applications, the portion immediately proximal to the given location along portion L has a greater cross-sectional area than the frame at the given location, due to the frustoconical shape of the expandable frame. Typically, the greater cross-sectional area of the portion immediately proximal to the given location along portion L relative to the cross-sectional area of the frame at the given location, reduces distal migration of the prosthetic valve toward the subject's left ventricle.

For some applications, the location along portion L at which to couple prosthetic valve <b>80</b> to valve support <b>40</b> is selected, based upon a distance D between protrusions <b>84</b> and annular element <b>44</b> that would result from coupling the prosthetic valve to the annular element at that location. For example, the location along portion L at which to couple prosthetic valve <b>80</b> to valve support <b>40</b> may be selected, such that distance D is such as to anchor the prosthetic valve to the patient's native valve by squeezing the patient's native valve leaflets between the protrusions and the annular element, and/or by ensnaring the patient's chordae tendinae between the protrusions and the annular element. Alternatively or additionally, the location along portion L at which to couple prosthetic valve <b>80</b> to valve support <b>40</b> may be selected, such that distance D is such that protrusions <b>84</b> (a) prevent proximal migration of the valve into the patient's atrium, while (b) allowing movement of the native leaflets with respect to the frame of the prosthetic valve. Typically, the location along portion L is selected such that distance D is such that the valve may be stopped from proximally migrating into the atrium, by the protrusions preventing the distal end of the valve from migrating further proximally than edges of native leaflets of the valve, while the protrusions allow movement of the native leaflets with respect to the frame of the prosthetic valve by not generally squeezing the native leaflets between the protrusions and the frame of the valve. For some applications, by allowing movement of the native leaflets with respect to the frame of the prosthetic valve sealing of the native leaflets against the outer surface of the frame of the prosthetic valve is facilitated, in accordance with the techniques described hereinabove with reference to <figref idref="DRAWINGS">FIG. 10</figref>.

Subsequent to the placement of the prosthetic valve at the native valve, overtube <b>70</b>, and pushing elements <b>52</b><i>a</i>, <b>52</b><i>b</i>, and <b>52</b><i>c </i>are removed from the patient's body, as shown in <figref idref="DRAWINGS">FIG. 15E</figref>, which shows the prosthetic valve in its deployed state.

Reference is now made to <figref idref="DRAWINGS">FIGS. 16A-G</figref>, which are schematic illustrations of respective steps of an alternative procedure for deploying prosthetic valve <b>80</b>, in accordance with some applications of the present invention. As described hereinabove, with reference to <figref idref="DRAWINGS">FIGS. 7A-F</figref>, for some applications, a looped guide member <b>21</b> is looped through commissures <b>8</b> and <b>10</b> in a manner in which the guide member defines a looped portion between commissures <b>8</b> and <b>10</b>. For some applications, the looped guide member has steering functionality. The steering functionality of the looped guide member is used to guide the guide member to the commissures, and/or to guide other portions of the apparatus to the native valve and/or to ventricle <b>6</b>. The looped guide member is typically advanced toward ventricle <b>6</b> over guidewire <b>306</b>, e.g., as described hereinabove with reference to <figref idref="DRAWINGS">FIG. 7A</figref>.

Typically, as shown in <figref idref="DRAWINGS">FIG. 16A</figref>, portions <b>21</b><i>a </i>and <b>21</b><i>b </i>of the looped guide member are independently manipulable. The portions of the looped guide member are manipulated (e.g., expanded and contracted) so as to guide the looped guide member to the subject's native valve, by pushing against inner surfaces of the subject's heart, as shown in <figref idref="DRAWINGS">FIG. 16A</figref>.

<figref idref="DRAWINGS">FIG. 16B</figref> shows the looped guide member looped through commissures <b>8</b> and <b>10</b> of the subject's native valve. When the looped guide member is disposed at the native valve, the guide member is used to guide and to anchor valve support <b>40</b>, as described hereinbelow.

As shown in <figref idref="DRAWINGS">FIG. 16C</figref>, for some applications, looped guide member <b>21</b> is coupled to valve support <b>40</b> via coupling wires <b>500</b> and coupling mechanisms <b>502</b>. For example, as shown, the coupling mechanism may include an anchor. A suture <b>504</b>, or a different looped element, protrudes from the bottom surface of annular element <b>44</b> of valve support <b>40</b> and is anchored by the anchor. Thus, when looped guide member <b>21</b> is pushed distally into ventricle <b>6</b>, the valve support is pulled against the annulus of the native valve by coupling wires <b>500</b> pulling on the valve support.

Typically, coupling mechanisms <b>502</b>, which are used to couple looped guide member <b>21</b> to valve support <b>40</b> are detachable coupling mechanisms. For example, as shown, the coupling mechanism may include an anchor that defines an opening <b>506</b> through which suture <b>504</b> is inserted. The opening is closed by a closing member <b>508</b>, such as a rod, or a wire. In order to detach the guide member from valve support, closing member <b>508</b> is opened (e.g., by being pulled proximally) such that suture <b>504</b> is released through opening <b>506</b>.

Subsequent to the placement of valve support <b>40</b> at the native valve, prosthetic atrioventricular valve <b>80</b> is placed in ventricle <b>6</b>, by advancing overtube <b>70</b> into the ventricle, as shown in <figref idref="DRAWINGS">FIG. 16D</figref>. <figref idref="DRAWINGS">FIG. 16E</figref> shows prosthetic valve having been partially deployed in the ventricle. Following the partial deployment of valve <b>80</b> in ventricle <b>6</b>, overtube <b>70</b> is pulled proximally to pull valve <b>80</b> proximally such that annular element <b>44</b> of valve support <b>40</b> surrounds a proximal portion of prosthetic valve <b>80</b>, as shown in <figref idref="DRAWINGS">FIGS. 16E-F</figref>. Valve <b>80</b> has a tendency to expand such that valve <b>80</b> is held in place with respect to valve support <b>40</b> responsively to radial forces acted upon valve support <b>40</b> by prosthetic valve <b>80</b>.

During the pulling back of overtube <b>70</b>, looped guide member <b>21</b> is pushed distally, thereby pulling valve support <b>40</b> against the native annulus and providing a counter force against which overtube <b>70</b> is pulled back. For some applications, pulling of the valve support against the native annulus is such that it is not necessary to use anchors for anchoring the valve support to the native valve during the coupling of the prosthetic valve to the valve support. Alternatively, in addition to the pulling of the valve support against the native annulus providing a counter force against which the prosthetic valve is pulled, anchors are used to anchor the valve support to the native valve during the coupling of the prosthetic valve to the valve.

<figref idref="DRAWINGS">FIG. 16G</figref> shows prosthetic valve <b>80</b> and valve support <b>40</b> coupled to the native valve. At this stage, coupling mechanism <b>502</b> is typically detached from the valve support. For example, as shown, closing member <b>508</b> is pulled, such that opening <b>506</b> is opened, and suture <b>504</b> is released through the opening. Subsequently, looped guide member <b>21</b>, and overtube <b>70</b> are removed from the subject's body, as shown in <figref idref="DRAWINGS">FIG. 16H</figref>, which shows the prosthetic valve in its deployed state.

As described with reference to <figref idref="DRAWINGS">FIGS. 16A-H</figref>, for some applications, prosthetic valve <b>80</b> is coupled to a native valve, by (a) placing valve support <b>40</b> on an atrial side of the native annulus, (b) placing the prosthetic valve inside the ventricle, and then, simultaneously, (c) pulling the prosthetic valve toward the atrium, and pulling the valve support toward the ventricle.

Reference is now made to <figref idref="DRAWINGS">FIGS. 17A-C</figref>, which are schematic illustrations of leaflets <b>82</b> of prosthetic valve <b>80</b>, in accordance with some applications of the present invention. <figref idref="DRAWINGS">FIG. 17A</figref> shows the leaflets before the leaflets are sutured to expandable frame <b>79</b> of the valve. As shown, in this state, the leaflets have a diameter D<b>1</b>, and the leaflets are not fully closed. <figref idref="DRAWINGS">FIG. 17B</figref> shows the leaflets when the leaflets have been sutured to expandable frame <b>79</b> of the prosthetic valve. The expandable frame constrains the leaflets, such that the leaflets define a diameter D<b>2</b>, which is smaller than diameter D<b>1</b>, thereby closing the leaflets. <figref idref="DRAWINGS">FIG. 17C</figref> shows the leaflets subsequent to the deployment of valve <b>80</b> inside valve support <b>40</b>, the valve support constraining the expansion of the prosthetic valve. Due to the valve support constraining the prosthetic valve, the valve leaflets are constrained so as define a diameter D<b>3</b>, which is smaller than diameter D<b>2</b>.

Typically, valve leaflets <b>82</b> are selected to be used in prosthetic valve <b>80</b>, the leaflets being sized such that both at diameter D<b>2</b> (when the leaflets are constrained by expandable frame <b>79</b> but are not constrained by valve support <b>40</b>) and at diameter D<b>3</b> (when the leaflets are constrained by both expandable frame <b>79</b> and valve support <b>40</b>), the valve leaflets fully coapt.

Reference is now made to <figref idref="DRAWINGS">FIGS. 18A-B</figref> which are schematic illustrations of a system <b>220</b> comprising a valve support <b>240</b> comprising an annular element <b>244</b> and a cylindrical element <b>242</b> and one or more (e.g., a plurality, as shown, of) tissue anchors <b>230</b>, in accordance with some applications of the present invention. Annular element <b>244</b> has an upper surface <b>241</b> and a lower surface <b>243</b>. Tissue anchors <b>230</b> are coupled to lower surface <b>234</b> of annular element. Tissue anchors <b>230</b> are shaped so as to define a pointed distal tip <b>234</b> and one or more (e.g., three, as shown) radially-expandable prongs <b>232</b>. Prongs <b>232</b> comprise a flexible metal, e.g., nitinol or stainless steel, and have a tendency to expand radially. Anchors <b>230</b> facilitate coupling of valve support <b>240</b> to annulus <b>11</b> of native valve <b>5</b>, such as the mitral valve or the tricuspid valve. Anchors <b>230</b> are typically distributed approximately evenly around lower surface <b>243</b> of annular element <b>244</b>. For some applications, one or more anchors <b>230</b> are disposed at a location of annular element that is configured to be positioned adjacently to commissures <b>8</b> and <b>10</b> of valve <b>5</b>.

Reference is now made to <figref idref="DRAWINGS">FIGS. 19A-D</figref> which are schematic illustrations of valve support <b>240</b> being implanted at valve <b>5</b> and the subsequent coupling of prosthetic valve <b>80</b> to valve support <b>240</b>. Valve support <b>240</b> is advanced toward native valve <b>5</b> by pushing elements <b>52</b><i>a </i>and <b>52</b><i>b</i>, as described hereinabove with respect to valve support <b>40</b> with reference to <figref idref="DRAWINGS">FIGS. 2D-F</figref>. In response to the pushing force to valve support <b>240</b> by pushing elements <b>52</b><i>a </i>and <b>52</b><i>b</i>, anchors <b>230</b> are pushed into tissue of annulus <b>11</b> of valve <b>5</b>. The pushing force by elements <b>52</b><i>a </i>and <b>52</b><i>b </i>is sufficient to implant each one of the plurality of anchors that are distributed around lower surface <b>243</b> of annular element <b>244</b>.

<figref idref="DRAWINGS">FIG. 19A</figref> shows initial penetration of tissue of annulus <b>11</b> by pointed distal tip <b>234</b> of anchor <b>230</b>. In <figref idref="DRAWINGS">FIG. 19B</figref>, the initial force of the tissue on prongs <b>232</b> pushes inwardly prongs <b>232</b>. Finally, in <figref idref="DRAWINGS">FIG. 19C</figref>, prongs <b>232</b> expand within tissue of annulus <b>11</b> to assume a flower shape and a larger surface area to restrict proximal motion of anchor <b>230</b> and thereby anchor valve support <b>240</b> in tissue of annulus <b>11</b>. As shown in <figref idref="DRAWINGS">FIGS. 19A-C</figref>, the cylindrical element of valve support <b>240</b> pushes aside native leaflets <b>12</b> and <b>14</b> of valve <b>5</b>.

In <figref idref="DRAWINGS">FIG. 19D</figref>, prosthetic valve <b>80</b> is coupled to valve support <b>240</b>, in a manner as described hereinabove.

It is noted that, in general, prosthetic valve <b>80</b> is self-expandable. When the prosthetic valve is deployed (i.e., when the valve self-expands) inside the subject's heart, the expansion of the valve is typically constrained by valve support <b>40</b>. Further typically, the expansion of the valve is not constrained by the native annulus.

For some application, by constraining the expansion of the prosthetic valve with the valve support, the deployed cross-sectional area of the prosthetic valve may be fixed at a given area, by using a valve support that defines a hole having the given cross-sectional area. As described hereinabove with reference to <figref idref="DRAWINGS">FIG. 10</figref>, for some applications, the area defined by the native annulus is measured, and the cross-sectional area of the prosthetic valve that is to be deployed in the valve is selected based upon the measured area of the native annulus. Alternatively or additionally, valve support <b>40</b> is selected based upon the measured area of the native annulus.

For example, a valve support may be selected such that the valve support constrains the expansion of the prosthetic valve, when the cross-sectional area of the prosthetic valve is less than 90% (e.g., less than 80%, or less than 60%) of the area defined by the native annulus. As described hereinabove, for some applications, placing a prosthetic valve inside the native valve with the dimensions of the native valve annulus and the prosthetic valve being as described, facilitates sealing of the prosthetic valve with respect to the native valve, by the native valve leaflets closing around the outer surface of the prosthetic valve.

For some applications, the expansion of prosthetic valve <b>80</b> against valve support <b>40</b> couples the prosthetic valve to the valve support, and/or couples the valve and the valve support to the native mitral valve. Typically, the expansion of the prosthetic valve against the valve support couples the prosthetic valve to the valve support, and sandwiching of the native valve leaflets between protrusions from the distal end of the valve and the valve support couples the prosthetic valve and the valve support to the native valve.

Reference is now made to <figref idref="DRAWINGS">FIGS. 1A-D</figref>, <b>2</b>A-K, <b>3</b>A-D, <b>4</b>A-C, <b>5</b>A-D, <b>6</b>A-B, <b>7</b>A-F, <b>8</b>A-C, <b>9</b>A-H, <b>10</b>, <b>11</b>A-D, and <b>12</b>A-C. It is to be noted that valve support <b>40</b> may be invertible as described hereinabove with respect to valve supports <b>140</b> and <b>300</b>, with reference to <figref idref="DRAWINGS">FIGS. 8A-C</figref>, and <b>9</b>A-H. It is to be further noted that valve supports <b>140</b> and <b>300</b> may be used in conjunction with one or more of the elements for facilitating sealing of the native valve with respect to a valve support or a valve that is described with reference to <figref idref="DRAWINGS">FIGS. 3A-D</figref>, <b>4</b>A-C, <b>5</b>A-D, and <b>6</b>A-B. For example, valve supports <b>140</b> and <b>300</b> may be used with sealing balloon <b>90</b>, commissural anchors <b>100</b><i>a </i>and <b>100</b><i>b</i>, grasping elements <b>106</b><i>a </i>and <b>106</b><i>b</i>, and/or sealing material <b>110</b>. It is still further noted that valve supports <b>140</b> and <b>300</b> may be implanted using a guide member that defines a looped portion between commissures <b>8</b> and <b>10</b>, as described with reference to <figref idref="DRAWINGS">FIGS. 7A-F</figref>. It is further noted that any of the applications described herein can be used in conjunction with valves having configurations as described with reference to <figref idref="DRAWINGS">FIGS. 10-12C</figref>.

The systems described herein are advanced toward valve <b>5</b> in a transcatheter procedure, as shown. It is to be noted, however, that the systems described herein may be advanced using any suitable procedure, e.g., minimally-invasively (e.g., via a transeptal, a transatrial, a transapical, and/or a transaortic approach), or using an open-heart procedure. It is to be further noted that valve supports and prosthetic valves herein may be used to replace native mitral valves or native tricuspid valves.

Reference is now made to <figref idref="DRAWINGS">FIGS. 20A-B</figref>, which are schematic illustrations of valve support <b>40</b> and prosthetic valve <b>80</b> coupled respectively to a tricuspid valve, and to an aortic valve, in accordance with some applications of the present invention. For some applications, valve support <b>40</b> and prosthetic valve <b>80</b> are deployed at a tricuspid valve and/or at an aortic valve using generally similar techniques to those described herein with reference to the deployment of the valve support and the prosthetic valve at the mitral valve, mutatis mutandis.

It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes both combinations and subcombinations of the various features described hereinabove, as well as variations and modifications thereof that are not in the prior art, which would occur to persons skilled in the art upon reading the foregoing description.